|
1
|
Radaelli R, Rech A, Molinari T, Markarian AM, Petropoulou M, Granacher U, Hortobágyi T, Lopez P. Effects of Resistance Training Volume on Physical Function, Lean Body Mass and Lower-Body Muscle Hypertrophy and Strength in Older Adults: A Systematic Review and Network Meta-analysis of 151 Randomised Trials. Sports Med 2025; 55:167-192. [PMID: 39405023 DOI: 10.1007/s40279-024-02123-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/19/2024] [Indexed: 02/03/2025]
Abstract
BACKGROUND The optimal prescription and precise recommendations of resistance training volume for older adults is unclear in the current literature. In addition, the interactions between resistance training volume and program duration as well as physical health status remain to be determined when assessing physical function, muscle size and hypertrophy and muscle strength adaptations in older adults. OBJECTIVES This study aimed to determine which resistance training volume is the most effective in improving physical function, lean body mass, lower-limb muscle hypertrophy and strength in older adults. Additionally, we examined whether effects were moderated by intervention duration (i.e. short term, < 20 weeks; medium-to-long term, ≥ 20 weeks) and physical health status (i.e. physically healthy, physically impaired, mixed physically healthy and physically impaired; PROSPERO identifier: CRD42023413209). METHODS CINAHL, Embase, LILACS, PubMed, Scielo, SPORTDiscus and Web of Science databases were searched up to April 2023. Eligible randomised trials examined the effects of supervised resistance training in older adults (i.e. ≥ 60 years). Resistance training programs were categorised as low (LVRT), moderate (MVRT) and high volume (HVRT) on the basis of terciles of prescribed weekly resistance training volume (i.e. product of frequency, number of exercises and number of sets) for full- and lower-body training. The primary outcomes for this review were physical function measured by fast walking speed, timed up and go and 6-min walking tests; lean body mass and lower-body muscle hypertrophy; and lower-body muscle strength measured by knee extension and leg press one-repetition maximum (1-RM), isometric muscle strength and isokinetic torque. A random-effects network meta-analysis was undertaken to examine the effects of different resistance training volumes on the outcomes of interest. RESULTS We included a total of 161 articles describing 151 trials (n = 6306). LVRT was the most effective for improving timed up and go [- 1.20 standardised mean difference (SMD), 95% confidence interval (95% CI): - 1.57 to - 0.82], 6-min walk test (1.03 SMD, 95% CI: 0.33-1.73), lean body mass (0.25 SMD, 95% CI: 0.10-0.40) and muscle hypertrophy (0.40 SMD, 95% CI: 0.25-0.54). Both MVRT and HVRT were the most effective for improving lower-limb strength, while only HVRT was effective in increasing fast walking speed (0.40 SMD, 95% CI: - 0.57 to 0.14). Regarding the moderators, our results were independent of program duration and mainly observed for healthy older adults, while evidence was limited for those who were physically impaired. CONCLUSIONS A low resistance training volume can substantially improve healthy older adults' physical function and benefits lean mass and muscle size independently of program duration, while a higher volume seems to be necessary for achieving greater improvements in muscle strength. A low volume of resistance training should be recommended in future exercise guidelines, particularly for physically healthy older adults targeting healthy ageing.
Collapse
Affiliation(s)
- Régis Radaelli
- Egas Moniz Center for Interdisciplinary Research (CiiEM), Egas Moniz School of Health and Science, Caparica, Almada, Portugal.
| | - Anderson Rech
- Curso de Educação Física, Universidade de Caxias do Sul, Caxias do Sul, Brazil
- Grupo de Pesquisa Em Exercício Para Populações Clínicas (GPCLIN), Universidade de Caxias do Sul, Caxias do Sul, Rio Grande do Sul, Brazil
| | - Talita Molinari
- Sport and Exercise Neuromechanics Group, Universidade Federal do Rio Grande, Rio Grande, Brazil
| | - Anna Maria Markarian
- Exercise Medicine Research Institute, Edith Cowan University, Joondalup, Australia
- School of Medical and Health Sciences, Edith Cowan University, Joondalup, Australia
| | - Maria Petropoulou
- Institute of Medical Biometry and Statistics, Faculty of Medicine and Medical Center, University of Freiburg, Freiburg, Germany
| | - Urs Granacher
- Department of Sport and Sport Science, Exercise and Human Movement Science, University of Freiburg, Freiburg, Germany
| | - Tibor Hortobágyi
- Department of Kinesiology, Hungarian University of Sports Science, Budapest, Hungary
- Center for Human Movement Sciences, University of Groningen Medical Center, Groningen, The Netherlands
- Institute of Sport Sciences and Physical Education, University of Pécs, Pécs, Hungary
- Department of Human Movement Sciences, University Medical Center Groningen, Groningen, The Netherlands
| | - Pedro Lopez
- Grupo de Pesquisa Em Exercício Para Populações Clínicas (GPCLIN), Universidade de Caxias do Sul, Caxias do Sul, Rio Grande do Sul, Brazil
- Pleural Medicine Unit, Institute for Respiratory Health, Perth, WA, Australia
- Programa de Pós-Graduação em Ciências da Saúde, Universidade de Caxias do Sul, Caxias do Sul, Rio Grande do Sul, Brazil
| |
Collapse
|
|
2
|
de Abreu DCC, Peres-Ueno MJ, Porto JM. Conceptual framework for the associations between trunk and lower limb muscle parameters and physical performance in community-dwelling older women. Braz J Phys Ther 2025; 29:101143. [PMID: 39644696 PMCID: PMC11665646 DOI: 10.1016/j.bjpt.2024.101143] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/27/2023] [Revised: 08/08/2024] [Accepted: 10/31/2024] [Indexed: 12/09/2024] Open
Abstract
BACKGROUND Muscle status plays an important role in the achievement of good physical performance. However, which muscle group and muscle parameters are associated with different physical tasks is not well defined. OBJECTIVE To determine the association between trunk and lower limb muscles and physical performance in community-dwelling older women. METHODS 118 older women, underwent an evaluation of physical performance, i.e., gait speed, Timed Up and Go (TUG), 5-times stand-to-sit (5TSST), forward and lateral step, and tandem gait, as well as a muscle performance evaluation with an isokinetic dynamometer to obtain the peak torque (PT), rate of torque development (RTD), and torque steadiness (TS) of the trunk, hip, knee, and ankle. RESULTS There were associations between physical performance and muscle variables. However, each physical task was associated with different muscle parameters. Gait speed is the motor task that requires the least muscle strength (i.e., PT), whereas 5TSST, forward and lateral steps require PT, RTD, and TS of different muscle groups. Lower limb muscles RTD also plays a role in TUG and gait speed performance. The ability to control a submaximal torque is mainly required for forward and lateral stepping tasks. The PT of trunk muscles is also important for better performance of clinical tests. CONCLUSION This conceptual framework may be a guide for the understanding of the association between physical performance and trunk and lower limb muscle functional parameters in older women and may help future longitudinal research to confirm causality and assist physical therapists in decision-making.
Collapse
Affiliation(s)
| | - Melise Jacon Peres-Ueno
- Program in Rehabilitation and Functional Performance, Ribeirão Preto School of Medicine, Universidade de São Paulo (USP), Ribeirão Preto, SP, Brazil
| | - Jaqueline Mello Porto
- Program in Rehabilitation and Functional Performance, Ribeirão Preto School of Medicine, Universidade de São Paulo (USP), Ribeirão Preto, SP, Brazil
| |
Collapse
|
|
3
|
de Santana DA, Scolfaro PG, Marzetti E, Cavaglieri CR. Lower extremity muscle hypertrophy in response to resistance training in older adults: Systematic review, meta-analysis, and meta-regression of randomized controlled trials. Exp Gerontol 2024; 198:112639. [PMID: 39579806 DOI: 10.1016/j.exger.2024.112639] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2024] [Revised: 10/25/2024] [Accepted: 11/18/2024] [Indexed: 11/25/2024]
Abstract
OBJECTIVES This study aimed to investigate the effects of resistance training (RT) on knee extensor muscle hypertrophy in adults 65 years and older. METHODS A systematic search was carried out in PubMed, Embase, and Scopus to review randomized controlled trials that assessed the effects of supervised RT on 1) muscle size, 2) fiber area, and 3) leg lean mass (LLM). Random-effects meta-analyses of standardized mean difference (SMD) and raw mean difference (RMD) for LLM were calculated. We performed a meta-regression to examine the interference of age, training volume, and duration on the results related to hypertrophy at muscle and fiber levels. RESULTS Thirty-two studies were included in the review, and 28 were meta-analyzed. The meta-analysis found a significant effect of RT on muscle size (SMD = 0.34; 95 % CI: 0.16-0.52; p < 0.001) and fiber area (SMD = 0.54; 95 % CI: 0.24-0.84; p < 0.001), but not on LLM (RMD = 0.22; 95 % CI: -0.22-0.66 p = 0.321). A subanalysis of studies that assessed quadriceps femoris size (excluding isolated quadriceps femoris muscles from the analysis) also revealed a significant effect of RT (95 % CI: 0.20-0.69; p < 0.001). Regression analysis indicated a significant influence of intervention duration on type II fiber area (p = 0.034), while no significant influence was detected for weekly sets or age for any outcome measure. CONCLUSIONS RT promotes muscle hypertrophy in older adults at both whole-muscle and fiber levels, with training duration potentially influencing the response. Measures of leg lean mass may not capture RT-induced adaptation.
Collapse
Affiliation(s)
- Davi Alves de Santana
- Laboratory of Exercise Physiology, Faculty of Physical Education, University of Campinas, Campinas, São Paulo, Brazil; Adventist University Center of São Paulo, São Paulo, Brazil
| | - Pedro Godoi Scolfaro
- Laboratory of Exercise Physiology, Faculty of Physical Education, University of Campinas, Campinas, São Paulo, Brazil
| | - Emanuele Marzetti
- Department of Geriatrics, Orthopedics and Rheumatology, Università Cattolica del Sacro Cuore, Rome, Italy; Fondazione Policlinico Universitario "Agostino Gemelli" IRCCS, Rome, Italy.
| | - Cláudia Regina Cavaglieri
- Laboratory of Exercise Physiology, Faculty of Physical Education, University of Campinas, Campinas, São Paulo, Brazil
| |
Collapse
|
|
4
|
Del Vecchio A, Enoka RM, Farina D. Specificity of early motor unit adaptations with resistive exercise training. J Physiol 2024; 602:2679-2688. [PMID: 38686581 DOI: 10.1113/jp282560] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2023] [Accepted: 04/10/2024] [Indexed: 05/02/2024] Open
Abstract
After exposure of the human body to resistive exercise, the force-generation capacity of the trained muscles increases significantly. Despite decades of research, the neural and muscular stimuli that initiate these changes in muscle force are not yet fully understood. The study of these adaptations is further complicated by the fact that the changes may be partly specific to the training task. For example, short-term strength training does not always influence the neural drive to muscles during the early phase (<100 ms) of force development in rapid isometric contractions. Here we discuss some of the studies that have investigated neuromuscular adaptations underlying changes in maximal force and rate of force development produced by different strength training interventions, with a focus on changes observed at the level of spinal motor neurons. We discuss the different motor unit adjustments needed to increase force or speed, and the specificity of some of the adaptations elicited by differences in the training tasks.
Collapse
Affiliation(s)
- Alessandro Del Vecchio
- Department Artificial Intelligence in Biomedical Engineering, Friedrich-Alexander University Erlangen-Nürnberg, Erlangen, Germany
| | - Roger Maro Enoka
- Department of Integrative Physiology, University of Colorado Boulder, Boulder, Colorado, USA
| | - Dario Farina
- Department of Bioengineering, Imperial College London, London, UK
| |
Collapse
|
|
5
|
Siddique U, Frazer AK, Avela J, Walker S, Ahtiainen JP, Howatson G, Tallent J, Kidgell DJ. Determining the cortical, spinal and muscular adaptations to strength-training in older adults: A systematic review and meta-analysis. Ageing Res Rev 2022; 82:101746. [PMID: 36223874 DOI: 10.1016/j.arr.2022.101746] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2022] [Revised: 09/30/2022] [Accepted: 10/05/2022] [Indexed: 01/31/2023]
Abstract
There are observable decreases in muscle strength as a result of ageing that occur from the age of 40, which are thought to occur as a result of changes within the neuromuscular system. Strength-training in older adults is a suitable intervention that may counteract the age-related loss in force production. The neuromuscular adaptations (i.e., cortical, spinal and muscular) to strength-training in older adults are largely equivocal and a systematic review with meta-analysis will serve to clarify the present circumstances regarding the benefits of strength-training in older adults. 20 studies entered the meta-analysis and were analysed using a random-effects model. A best evidence synthesis that included 36 studies was performed for variables that had insufficient data for meta-analysis. One study entered both. There was strong evidence that strength-training increases maximal force production, rate of force development and muscle activation in older adults. There was limited evidence for strength-training to improve voluntary-activation, the volitional-wave and spinal excitability, but strong evidence for increased muscle mass. The findings suggest that strength-training performed between 2 and 12 weeks increases strength, rate of force development and muscle activation, which likely improves motoneurone excitability by increased motor unit recruitment and improved discharge rates.
Collapse
Affiliation(s)
- Ummatul Siddique
- Monash Exercise Neuroplasticity Research Unit, Department of Physiotherapy, School of Primary and Allied Health Care, Faculty of Medicine, Nursing and Health Science, Monash University, Melbourne, Australia
| | - Ashlyn K Frazer
- Monash Exercise Neuroplasticity Research Unit, Department of Physiotherapy, School of Primary and Allied Health Care, Faculty of Medicine, Nursing and Health Science, Monash University, Melbourne, Australia
| | - Janne Avela
- NeuroMuscular Research Center, Faculty of Sport and Health Sciences, University of Jyväskylä, Finland
| | - Simon Walker
- NeuroMuscular Research Center, Faculty of Sport and Health Sciences, University of Jyväskylä, Finland
| | - Juha P Ahtiainen
- NeuroMuscular Research Center, Faculty of Sport and Health Sciences, University of Jyväskylä, Finland
| | - Glyn Howatson
- Department of Sport, Exercise and Rehabilitation, Northumbria University, Newcastle, UK; Water Research Group, North West University, Potchefstroom, South Africa
| | - Jamie Tallent
- Monash Exercise Neuroplasticity Research Unit, Department of Physiotherapy, School of Primary and Allied Health Care, Faculty of Medicine, Nursing and Health Science, Monash University, Melbourne, Australia; School of Sport, Rehabilitation and Exercise Sciences, University of Essex, Colchester, UK
| | - Dawson J Kidgell
- Monash Exercise Neuroplasticity Research Unit, Department of Physiotherapy, School of Primary and Allied Health Care, Faculty of Medicine, Nursing and Health Science, Monash University, Melbourne, Australia.
| |
Collapse
|
|
6
|
Satam AP, van der Leeden M, de Zwart A, Verberne S, Schrijvers JC, Hall M, Dekker J, Lems WF, Harlaar J, van der Esch M. The associations of knee extensor muscle steadiness with maximal voluntary torque and physical function in patients with knee osteoarthritis. Clin Biomech (Bristol, Avon) 2022; 99:105736. [PMID: 36041308 DOI: 10.1016/j.clinbiomech.2022.105736] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/30/2021] [Revised: 07/16/2022] [Accepted: 08/09/2022] [Indexed: 02/07/2023]
Abstract
BACKGROUND Muscle weakness is characteristic of knee osteoarthritis. Muscle steadiness may be an important adjunct to knee muscle strength in improving physical function in knee osteoarthritis. However, the role of muscle steadiness is uncertain. AIMS To determine the associations of knee extensor muscle steadiness with maximal voluntary torque and physical function in patients with knee osteoarthritis. METHODS Baseline data from 177 patients in a randomized clinical trial were used. Isokinetic knee extension torque was processed into maximal voluntary torque [Nm]. Muscle steadiness was expressed as the coefficient of variance [%] and as peak power frequency [Hz]. Physical function was assessed using the Western Ontario and McMaster Universities Osteoarthritis Index, the Get-Up-and-Go and Stair-climb tests. Associations were determined using regression analyses and adjusted for confounders. FINDINGS Lower muscle steadiness (i.e., higher coefficient of variance and peak power frequency) was associated with lower maximal voluntary torque (B = - 7.38, [-10.8, -3.95], R2 = 0.10 and B = -14.71, [-28.29, -1.13], R2 = 0.03, respectively). Higher coefficient of variance was associated with lower self-reported physical function (B = 1.14, [0.11,2.17], R2 = 0.03) and remained significant after adjusting for potential confounders. Peak power frequency was not associated with physical function. INTERPRETATION Low muscle steadiness was weakly associated with low muscle strength and poorer self-reported physical function. Muscle steadiness and muscle strength seem to be different attributes of muscle function. There is no convincing evidence that muscle steadiness is an important adjunct in studying physical function in patients with knee osteoarthritis.
Collapse
Affiliation(s)
- Anuja P Satam
- Reade Centre for Rehabilitation and Rheumatology, Amsterdam, the Netherlands
| | - Marike van der Leeden
- Reade Centre for Rehabilitation and Rheumatology, Amsterdam, the Netherlands; Amsterdam UMC, Vrije Universiteit Amsterdam, Department of Rehabilitation Medicine, Amsterdam Movement Sciences, de Boelelaan 1117, Amsterdam, the Netherlands
| | - Arjan de Zwart
- Reade Centre for Rehabilitation and Rheumatology, Amsterdam, the Netherlands
| | - Simon Verberne
- Reade Centre for Rehabilitation and Rheumatology, Amsterdam, the Netherlands
| | - Jim C Schrijvers
- Amsterdam UMC, Vrije Universiteit Amsterdam, Department of Rehabilitation Medicine, Amsterdam Movement Sciences, de Boelelaan 1117, Amsterdam, the Netherlands
| | - Michelle Hall
- Centre for Health, Exercise and Sports Medicine, Department of Physiotherapy, School of Health Sciences, The University of Melbourne, Melbourne, VIC, Australia
| | - Joost Dekker
- Amsterdam UMC, Vrije Universiteit Amsterdam, Department of Rehabilitation Medicine, Amsterdam Movement Sciences, de Boelelaan 1117, Amsterdam, the Netherlands
| | - Willem F Lems
- Reade Centre for Rehabilitation and Rheumatology, Amsterdam, the Netherlands; Amsterdam UMC, Vrije Universiteit Amsterdam, Department of Rheumatology, Amsterdam, the Netherlands
| | - Jaap Harlaar
- Delft University of Technology, Department of Biomechanical Engineering, Delft, the Netherlands; Erasmus Medical Centre, Department of Orthopaedics, Rotterdam, the Netherlands
| | - Martin van der Esch
- Reade Centre for Rehabilitation and Rheumatology, Amsterdam, the Netherlands; Centre of Expertise Urban vitality, Amsterdam University of Applied Sciences, Faculty of Health, Amsterdam, the Netherlands.
| |
Collapse
|
|
7
|
Toumi A, Smart R, Elie D, Bassement J, Leteneur S, Simoneau-Buessinger E, Jakobi J. Contribution of Achilles tendon mechanical properties to torque steadiness in persons with transfemoral amputation. Prosthet Orthot Int 2021; 45:170-177. [PMID: 33158397 DOI: 10.1177/0309364620966431] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/18/2020] [Accepted: 08/28/2020] [Indexed: 02/03/2023]
Abstract
BACKGROUND How Achilles tendon mechanics and plantar flexion strength and torque steadiness are altered in the intact leg of persons with trauma-related amputation is unknown. Understanding Achilles tendon mechanics following amputation will further inform rehabilitation approaches to enhance posture, balance, and force control. OBJECTIVE Conduct a pilot study to quantify plantar flexion maximal voluntary contraction torque, torque steadiness, and Achilles tendon mechanics in persons with unilateral trauma-related transfemoral amputation and controls without amputation. STUDY DESIGN Cross-sectional study. METHODS Isometric plantar flexion maximal voluntary contractions were performed with the intact leg of ten males with transfemoral amputation (48 ± 14 years) and the dominant leg of age-matched male controls without amputation. Torque steadiness was calculated as the coefficient of variation in torque over 6 s during submaximal tracking tasks (5%, 10%, 25%, 50%, and 75% maximal voluntary contraction). Achilles tendon elongation and cross-sectional area were recorded with ultrasound to calculate strain, stress, and stiffness. RESULTS Maximal voluntary contraction and torque steadiness did not differ between persons with amputation (90.6 ± 31.6 N m, 3.7 ± 2.0%) and controls (95.8 ± 26.8 N m, 2.9 ± 1.2%; p > 0.05). Tendon stiffness (21.1 ± 18.2 N/mm) and strain (5.2 ± 1.3%) did not differ between groups (p > 0.05). Tendon cross-sectional area was 10% greater in persons with amputation leading to 29% lower stress (p = 0.021). Maximal voluntary contraction was a predictor of a lower coefficient of variation in torque (R2 = 0.11, p < 0.05). CONCLUSION Persons with trauma-related transfemoral amputation do not differ in plantar flexion maximal voluntary contraction and torque steadiness of the intact leg compared with controls without amputation. Larger tendon cross-sectional area reduces stress and enables distribution of force across a greater area.
Collapse
Affiliation(s)
- Anis Toumi
- Laboratoire d'Automatique de Mécanique et d'Informatique industrielles et Humaines (LAMIH), UMR CNRS 8201, Université Polytechnique Hauts-de-France, Valenciennes, France.,School of Health and Exercise Sciences, University of British Columbia Okanagan, Kelowna, BC, Canada
| | - Rowan Smart
- School of Health and Exercise Sciences, University of British Columbia Okanagan, Kelowna, BC, Canada
| | - Dimitri Elie
- Laboratoire d'Automatique de Mécanique et d'Informatique industrielles et Humaines (LAMIH), UMR CNRS 8201, Université Polytechnique Hauts-de-France, Valenciennes, France
| | - Jennifer Bassement
- Laboratoire d'Automatique de Mécanique et d'Informatique industrielles et Humaines (LAMIH), UMR CNRS 8201, Université Polytechnique Hauts-de-France, Valenciennes, France
| | - Sébastien Leteneur
- Laboratoire d'Automatique de Mécanique et d'Informatique industrielles et Humaines (LAMIH), UMR CNRS 8201, Université Polytechnique Hauts-de-France, Valenciennes, France
| | - Emilie Simoneau-Buessinger
- Laboratoire d'Automatique de Mécanique et d'Informatique industrielles et Humaines (LAMIH), UMR CNRS 8201, Université Polytechnique Hauts-de-France, Valenciennes, France
| | - Jennifer Jakobi
- School of Health and Exercise Sciences, University of British Columbia Okanagan, Kelowna, BC, Canada
| |
Collapse
|
|
8
|
James E, Nichols S, Goodall S, Hicks KM, O'Doherty AF. The influence of resistance training on neuromuscular function in middle-aged and older adults: A systematic review and meta-analysis of randomised controlled trials. Exp Gerontol 2021; 149:111320. [PMID: 33774145 DOI: 10.1016/j.exger.2021.111320] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2021] [Revised: 03/16/2021] [Accepted: 03/18/2021] [Indexed: 10/21/2022]
Abstract
BACKGROUND Deterioration of neuromuscular function is a major mechanism of age-related strength loss. Resistance training (RT) improves muscle strength and mass. However, the effects of RT on neuromuscular adaptations in middle-aged and older adults are unclear. METHODS Randomised controlled RT interventions (≥2 weeks) involving adults aged ≥50 years were identified. Primary outcome measures were voluntary activation (VA), electromyographic (EMG) activity during maximal voluntary contraction (MVC), and antagonist coactivation. Data were pooled using a weighted random-effect model. Sub-analyses were conducted by muscle or muscle group and health status of participants. Sensitivity analysis was based on study quality. P < 0.05 indicated statistical significance. RESULTS Twenty-seven studies were included. An effect was found for VA (standardised mean difference [SMD] 0.54, 0.01 to 1.07, P = 0.04), This result remained significant following sensitivity analysis involving only studies that were low risk of bias. Subgroup analyses showed an effect for plantar flexor VA (SMD 1.13, 0.20 to 2.06, P = 0.02) and VA in healthy participants (SMD 1.04, 0.32 to 1.76, P = 0.004). There was no effect for EMG activity or antagonist coactivation of any muscle group (P > 0.05). DISCUSSION Resistance training did not alter EMG activity or antagonist coactivation in older adults. Sensitivity analysis resulted in the effect for VA remaining significant, indicating that this finding was not dependent on study quality. Studies predominantly involved healthy older adults (78%), limiting the generalisability of these findings to clinical cohorts. Future research should determine the effects of RT on neuromuscular function in people with sarcopenia and age-related syndromes.
Collapse
Affiliation(s)
- Emily James
- Department of Sport, Exercise and Rehabilitation, Northumbria University, Newcastle-Upon-Tyne, United Kingdom.
| | - Simon Nichols
- Sport and Physical Activity Research Group, Sheffield Hallam University, Sheffield, United Kingdom; Advanced Wellbeing Research Centre, Sheffield Hallam University, Sheffield, United Kingdom
| | - Stuart Goodall
- Department of Sport, Exercise and Rehabilitation, Northumbria University, Newcastle-Upon-Tyne, United Kingdom
| | - Kirsty M Hicks
- Department of Sport, Exercise and Rehabilitation, Northumbria University, Newcastle-Upon-Tyne, United Kingdom
| | - Alasdair F O'Doherty
- Department of Sport, Exercise and Rehabilitation, Northumbria University, Newcastle-Upon-Tyne, United Kingdom
| |
Collapse
|
|
9
|
Enoka RM, Farina D. Force Steadiness: From Motor Units to Voluntary Actions. Physiology (Bethesda) 2021; 36:114-130. [DOI: 10.1152/physiol.00027.2020] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Voluntary actions are controlled by the synaptic inputs that are shared by pools of spinal motor neurons. The slow common oscillations in the discharge times of motor units due to these synaptic inputs are strongly correlated with the fluctuations in force during submaximal isometric contractions (force steadiness) and moderately associated with performance scores on some tests of motor function. However, there are key gaps in knowledge that limit the interpretation of differences in force steadiness.
Collapse
Affiliation(s)
- Roger M. Enoka
- Department of Integrative Physiology, University of Colorado Boulder, Colorado
| | - Dario Farina
- Department of Bioengineering, Faculty of Engineering, Imperial College London, London, United Kingdom
| |
Collapse
|
|
10
|
Corticomuscular Coherence and Motor Control Adaptations after Isometric Maximal Strength Training. Brain Sci 2021; 11:brainsci11020254. [PMID: 33670532 PMCID: PMC7922221 DOI: 10.3390/brainsci11020254] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2021] [Revised: 02/05/2021] [Accepted: 02/09/2021] [Indexed: 11/16/2022] Open
Abstract
Strength training (ST) induces corticomuscular adaptations leading to enhanced strength. ST alters the agonist and antagonist muscle activations, which changes the motor control, i.e., force production stability and accuracy. This study evaluated the alteration of corticomuscular communication and motor control through the quantification of corticomuscular coherence (CMC) and absolute (AE) and variable error (VE) of the force production throughout a 3 week Maximal Strength Training (MST) intervention specifically designed to strengthen ankle plantarflexion (PF). Evaluation sessions with electroencephalography, electromyography, and torque recordings were conducted pre-training, 1 week after the training initiation, then post-training. Training effect was evaluated over the maximal voluntary isometric contractions (MVIC), the submaximal torque production, AE and VE, muscle activation, and CMC changes during submaximal contractions at 20% of the initial and daily MVIC. MVIC increased significantly throughout the training completion. For submaximal contractions, agonist muscle activation decreased over time only for the initial torque level while antagonist muscle activation, AE, and VE decreased over time for each torque level. CMC remained unaltered by the MST. Our results revealed that neurophysiological adaptations are noticeable as soon as 1 week post-training. However, CMC remained unaltered by MST, suggesting that central motor adaptations may take longer to be translated into CMC alteration.
Collapse
|
|
11
|
Klarod K, Singsanan S, Thamwiriyasati N, Ladawan S, Luangpon N, Boonsiri P, Burtscher M. Effects of Qigong exercise on muscle strengths and oxidative stress/antioxidant responses in young sedentary females: a quasi-experimental study. J Exerc Rehabil 2020; 16:418-426. [PMID: 33178643 PMCID: PMC7609847 DOI: 10.12965/jer.2040620.310] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2020] [Accepted: 09/10/2020] [Indexed: 11/22/2022] Open
Abstract
Regular exercise is associated with the production of small amounts of oxidative stress which might promote individual antioxidant capacity contributing to favorable training effects potentially interrelated with skeletal muscle strength. Therefore, the present study was aimed at evaluating effects of an 8-week Qigong exercise training on muscle strengths associated with responses of oxidative stress and antioxidants in young sedentary females. A total of 41 sedentary women were allocated to the Qigong exercise group (QG, N=20) or to the control group (CG, N=21). After 8 weeks of Qigong training, back and leg strength was significantly improved compared to baseline and the CG (P<0.05). Plasma oxidative stress levels were reduced and total antioxidant capacity was enhanced in the QG compared to the CG (P<0.05). Correlation analyses revealed that improvements in muscle strength (including both groups) were associated with changes in the levels of oxidative stress (reduction) and antioxidants (elevation). The presented findings indicate that strength training effects seem at least partly to be interrelated with alterations of the oxidant-antioxidant balance generated by the 8-week Qigong training in young sedentary females.
Collapse
Affiliation(s)
- Kultida Klarod
- Department of Physical Therapy, Faculty of Allied Health Sciences, Burapha University, Chonburi, Thailand
| | - Sanita Singsanan
- Department of Medical Technology, Faculty of Allied Health Sciences, Burapha University, Chonburi, Thailand
| | - Niramon Thamwiriyasati
- Department of Medical Technology, Faculty of Allied Health Sciences, Burapha University, Chonburi, Thailand
| | - Suphannika Ladawan
- Department of Physical Therapy, School of Allied Health Sciences, University of Phayao, Phayao, Thailand
| | - Nongnuch Luangpon
- Department of Physical Therapy, Faculty of Allied Health Sciences, Burapha University, Chonburi, Thailand
| | - Patcharee Boonsiri
- Department of Biochemistry, Faculty of Medicine, Khon Kaen University, Khon Kaen, Thailand
| | - Martin Burtscher
- Department of Sport Science, Medical Section, Faculty of Psychology and Sport Science, University of Innsbruck, Innsbruck, Austria
| |
Collapse
|
|
12
|
Oranchuk DJ, Storey AG, Nelson AR, Cronin JB. Scientific Basis for Eccentric Quasi-Isometric Resistance Training: A Narrative Review. J Strength Cond Res 2020; 33:2846-2859. [PMID: 31361732 DOI: 10.1519/jsc.0000000000003291] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Oranchuk, DJ, Storey, AG, Nelson, AR, and Cronin, JB. The scientific basis for eccentric quasi-isometric resistance training: A narrative review. J Strength Cond Res 33(10): 2846-2859, 2019-Eccentric quasi-isometric (EQI) resistance training involves holding a submaximal, yielding isometric contraction until fatigue causes muscle lengthening and then maximally resisting through a range of motion. Practitioners contend that EQI contractions are a powerful tool for the development of several physical qualities important to health and sports performance. In addition, several sports involve regular quasi-isometric contractions for optimal performance. Therefore, the primary objective of this review was to synthesize and critically analyze relevant biological, physiological, and biomechanical research and develop a rationale for the value of EQI training. In addition, this review offers potential practical applications and highlights future areas of research. Although there is a paucity of research investigating EQIs, the literature on responses to traditional contraction types is vast. Based on the relevant literature, EQIs may provide a practical means of increasing total volume, metabolite build-up, and hormonal signaling factors while safely enduring large quantities of mechanical tension with low levels of peak torque. Conversely, EQI contractions likely hold little neuromuscular specificity to high velocity or power movements. Therefore, EQI training seems to be effective for improving musculotendinous morphological and performance variables with low injury risk. Although speculative due to the limited specific literature, available evidence suggests a case for future experimentation.
Collapse
Affiliation(s)
- Dustin J Oranchuk
- Sports Performance Research Institute New Zealand, Auckland University of Technology, Auckland, New Zealand
| | - Adam G Storey
- Sports Performance Research Institute New Zealand, Auckland University of Technology, Auckland, New Zealand
| | - André R Nelson
- Institute for Health and Sport, Victoria University, Melbourne, Australia
| | - John B Cronin
- Sports Performance Research Institute New Zealand, Auckland University of Technology, Auckland, New Zealand.,School of Health and Medical Science, Edith Cowan University, Perth, Australia
| |
Collapse
|
|
13
|
Fragala MS, Cadore EL, Dorgo S, Izquierdo M, Kraemer WJ, Peterson MD, Ryan ED. Resistance Training for Older Adults: Position Statement From the National Strength and Conditioning Association. J Strength Cond Res 2019; 33:2019-2052. [PMID: 31343601 DOI: 10.1519/jsc.0000000000003230] [Citation(s) in RCA: 626] [Impact Index Per Article: 104.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Fragala, MS, Cadore, EL, Dorgo, S, Izquierdo, M, Kraemer, WJ, Peterson, MD, and Ryan, ED. Resistance training for older adults: position statement from the national strength and conditioning association. J Strength Cond Res 33(8): 2019-2052, 2019-Aging, even in the absence of chronic disease, is associated with a variety of biological changes that can contribute to decreases in skeletal muscle mass, strength, and function. Such losses decrease physiologic resilience and increase vulnerability to catastrophic events. As such, strategies for both prevention and treatment are necessary for the health and well-being of older adults. The purpose of this Position Statement is to provide an overview of the current and relevant literature and provide evidence-based recommendations for resistance training for older adults. As presented in this Position Statement, current research has demonstrated that countering muscle disuse through resistance training is a powerful intervention to combat the loss of muscle strength and muscle mass, physiological vulnerability, and their debilitating consequences on physical functioning, mobility, independence, chronic disease management, psychological well-being, quality of life, and healthy life expectancy. This Position Statement provides evidence to support recommendations for successful resistance training in older adults related to 4 parts: (a) program design variables, (b) physiological adaptations, (c) functional benefits, and (d) considerations for frailty, sarcopenia, and other chronic conditions. The goal of this Position Statement is to a) help foster a more unified and holistic approach to resistance training for older adults, b) promote the health and functional benefits of resistance training for older adults, and c) prevent or minimize fears and other barriers to implementation of resistance training programs for older adults.
Collapse
Affiliation(s)
| | - Eduardo L Cadore
- School of Physical Education, Physiotherapy and Dance, Exercise Research Laboratory, Federal University of Rio Grande do Sul, Porto Alegre, Brazil
| | - Sandor Dorgo
- Department of Kinesiology, University of Texas at El Paso, El Paso, Texas
| | - Mikel Izquierdo
- Department of Health Sciences, Public University of Navarre, CIBER of Frailty and Healthy Aging (CIBERFES), Navarrabiomed, Pamplona, Navarre, Spain
| | - William J Kraemer
- Department of Human Sciences, The Ohio State University, Columbus, Ohio
| | - Mark D Peterson
- Department of Physical Medicine and Rehabilitation, University of Michigan-Medicine, Ann Arbor, Michigan
| | - Eric D Ryan
- Department of Exercise and Sport Science, University of North Carolina-Chapel Hill, Chapel Hill, North Carolina
| |
Collapse
|
|
14
|
Gharahdaghi N, Rudrappa S, Brook MS, Idris I, Crossland H, Hamrock C, Abdul Aziz MH, Kadi F, Tarum J, Greenhaff PL, Constantin-Teodosiu D, Cegielski J, Phillips BE, Wilkinson DJ, Szewczyk NJ, Smith K, Atherton PJ. Testosterone therapy induces molecular programming augmenting physiological adaptations to resistance exercise in older men. J Cachexia Sarcopenia Muscle 2019; 10:1276-1294. [PMID: 31568675 PMCID: PMC6903447 DOI: 10.1002/jcsm.12472] [Citation(s) in RCA: 57] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/22/2019] [Revised: 05/14/2019] [Accepted: 06/12/2019] [Indexed: 01/30/2023] Open
Abstract
BACKGROUND The andropause is associated with declines in serum testosterone (T), loss of muscle mass (sarcopenia), and frailty. Two major interventions purported to offset sarcopenia are anabolic steroid therapies and resistance exercise training (RET). Nonetheless, the efficacy and physiological and molecular impacts of T therapy adjuvant to short-term RET remain poorly defined. METHODS Eighteen non-hypogonadal healthy older men, 65-75 years, were assigned in a random double-blinded fashion to receive, biweekly, either placebo (P, saline, n = 9) or T (Sustanon 250 mg, n = 9) injections over 6 week whole-body RET (three sets of 8-10 repetitions at 80% one-repetition maximum). Subjects underwent dual-energy X-ray absorptiometry, ultrasound of vastus lateralis (VL) muscle architecture, and knee extensor isometric muscle force tests; VL muscle biopsies were taken to quantify myogenic/anabolic gene expression, anabolic signalling, muscle protein synthesis (D2 O), and breakdown (extrapolated). RESULTS Testosterone adjuvant to RET augmented total fat-free mass (P=0.007), legs fat-free mass (P=0.02), and appendicular fat-free mass (P=0.001) gains while decreasing total fat mass (P=0.02). Augmentations in VL muscle thickness, fascicle length, and quadriceps cross-section area with RET occured to a greater extent in T (P < 0.05). Sum strength (P=0.0009) and maximal voluntary contract (e.g. knee extension at 70°) (P=0.002) increased significantly more in the T group. Mechanistically, both muscle protein synthesis rates (T: 2.13 ± 0.21%·day-1 vs. P: 1.34 ± 0.13%·day-1 , P=0.0009) and absolute breakdown rates (T: 140.2 ± 15.8 g·day-1 vs. P: 90.2 ± 11.7 g·day-1 , P=0.02) were elevated with T therapy, which led to higher net turnover and protein accretion in the T group (T: 8.3 ± 1.4 g·day-1 vs. P: 1.9 ± 1.2 g·day-1 , P=0.004). Increases in ribosomal biogenesis (RNA:DNA ratio); mRNA expression relating to T metabolism (androgen receptor: 1.4-fold; Srd5a1: 1.6-fold; AKR1C3: 2.1-fold; and HSD17β3: two-fold); insulin-like growth factor (IGF)-1 signalling [IGF-1Ea (3.5-fold) and IGF-1Ec (three-fold)] and myogenic regulatory factors; and the activity of anabolic signalling (e.g. mTOR, AKT, and RPS6; P < 0.05) were all up-regulated with T therapy. Only T up-regulated mitochondrial citrate synthase activity (P=0.03) and transcription factor A (1.41 ± 0.2-fold, P=0.0002), in addition to peroxisome proliferator-activated receptor-γ co-activator 1-α mRNA (1.19 ± 0.21-fold, P=0.037). CONCLUSIONS Administration of T adjuvant to RET enhanced skeletal muscle mass and performance, while up-regulating myogenic gene programming, myocellular translational efficiency and capacity, collectively resulting in higher protein turnover, and net protein accretion. T coupled with RET is an effective short-term intervention to improve muscle mass/function in older non-hypogonadal men.
Collapse
Affiliation(s)
- Nima Gharahdaghi
- MRC-ARUK Centre for Musculoskeletal Ageing Research and Nottingham NIHR BRC, School of Medicine, University of Nottingham, Derby, UK
| | - Supreeth Rudrappa
- MRC-ARUK Centre for Musculoskeletal Ageing Research and Nottingham NIHR BRC, School of Medicine, University of Nottingham, Derby, UK
| | - Matthew S Brook
- MRC-ARUK Centre for Musculoskeletal Ageing Research and Nottingham NIHR BRC, School of Medicine, University of Nottingham, Derby, UK
| | - Iskandar Idris
- MRC-ARUK Centre for Musculoskeletal Ageing Research and Nottingham NIHR BRC, School of Medicine, University of Nottingham, Derby, UK
| | - Hannah Crossland
- MRC-ARUK Centre for Musculoskeletal Ageing Research and Nottingham NIHR BRC, School of Medicine, University of Nottingham, Derby, UK
| | - Claire Hamrock
- Institute of Food and Health, University College Dublin, Belfield, Dublin, Ireland
| | - Muhammad Hariz Abdul Aziz
- MRC-ARUK Centre for Musculoskeletal Ageing Research and Nottingham NIHR BRC, School of Medicine, University of Nottingham, Derby, UK
| | - Fawzi Kadi
- Division of Sports Sciences, School of Health and Medical Sciences, Örebro University, Örebro, Sweden
| | - Janelle Tarum
- Division of Sports Sciences, School of Health and Medical Sciences, Örebro University, Örebro, Sweden
| | - Paul L Greenhaff
- MRC-ARUK Centre for Musculoskeletal Ageing Research, School of Life Sciences, University of Nottingham, Nottingham, Nottingham, UK
| | - Dumitru Constantin-Teodosiu
- MRC-ARUK Centre for Musculoskeletal Ageing Research, School of Life Sciences, University of Nottingham, Nottingham, Nottingham, UK
| | - Jessica Cegielski
- MRC-ARUK Centre for Musculoskeletal Ageing Research and Nottingham NIHR BRC, School of Medicine, University of Nottingham, Derby, UK
| | - Bethan E Phillips
- MRC-ARUK Centre for Musculoskeletal Ageing Research and Nottingham NIHR BRC, School of Medicine, University of Nottingham, Derby, UK
| | - Daniel J Wilkinson
- MRC-ARUK Centre for Musculoskeletal Ageing Research and Nottingham NIHR BRC, School of Medicine, University of Nottingham, Derby, UK
| | - Nathaniel J Szewczyk
- MRC-ARUK Centre for Musculoskeletal Ageing Research and Nottingham NIHR BRC, School of Medicine, University of Nottingham, Derby, UK
| | - Kenneth Smith
- MRC-ARUK Centre for Musculoskeletal Ageing Research and Nottingham NIHR BRC, School of Medicine, University of Nottingham, Derby, UK
| | - Philip J Atherton
- MRC-ARUK Centre for Musculoskeletal Ageing Research and Nottingham NIHR BRC, School of Medicine, University of Nottingham, Derby, UK
| |
Collapse
|
|
15
|
Handsaker JC, Brown SJ, Petrovic M, Bowling FL, Rajbhandari S, Marple-Horvat DE, Boulton AJM, Reeves ND. Combined exercise and visual gaze training improves stepping accuracy in people with diabetic peripheral neuropathy. J Diabetes Complications 2019; 33:107404. [PMID: 31371130 DOI: 10.1016/j.jdiacomp.2019.07.001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/17/2019] [Revised: 06/20/2019] [Accepted: 07/02/2019] [Indexed: 12/27/2022]
Abstract
INTRODUCTION Patients with diabetes and diabetic peripheral neuropathy (DPN) place their feet with less accuracy whilst walking, which may contribute to the increased falls-risk. This study examines the effects of a multi-faceted intervention on stepping accuracy, in patients with diabetes and DPN. METHODS Forty participants began the study, of which 29 completed both the pre and post-intervention tests, 8 patients with DPN, 11 patients with diabetes but no neuropathy (D) and 10 healthy controls (C). Accuracy of stepping was measured pre- and post-intervention as participants walked along an irregularly arranged stepping walkway. Participants attended a one-hour session, once a week, for sixteen weeks, involving high-load resistance exercise and visual-motor training. RESULTS Patients who took part in the intervention improved stepping accuracy (DPN: +45%; D: +36%) (p < 0.05). The diabetic non-intervention (D-NI) group did not display any significant differences in stepping accuracy pre- to post- the intervention period (-7%). DISCUSSION The improved stepping accuracy observed in patients with diabetes and DPN as a result of this novel intervention, may contribute towards reducing falls-risk. This multi-faceted intervention presents promise for improving the general mobility and safety of patients during walking and could be considered for inclusion as part of clinical treatment programmes.
Collapse
Affiliation(s)
- Joseph C Handsaker
- Research Centre for Musculoskeletal Science and Sports Medicine, Department of Life Sciences, Faculty of Science & Engineering, Manchester Metropolitan University, Oxford Road, Manchester, United Kingdom
| | - Steven J Brown
- Research Centre for Musculoskeletal Science and Sports Medicine, Department of Life Sciences, Faculty of Science & Engineering, Manchester Metropolitan University, Oxford Road, Manchester, United Kingdom
| | - Milos Petrovic
- Research Centre for Movement Sciences, Department of Physiotherapy, Faculty of Medicine, University of Iceland, Reykjavik, Iceland.
| | - Frank L Bowling
- Faculty of Medical and Human Sciences, University of Manchester, Manchester, United Kingdom
| | - Satyan Rajbhandari
- Lancashire Teaching Hospitals, Chorley and South Ribble Hospital, United Kingdom
| | - Dilwyn E Marple-Horvat
- Research Centre for Musculoskeletal Science and Sports Medicine, Department of Life Sciences, Faculty of Science & Engineering, Manchester Metropolitan University, Oxford Road, Manchester, United Kingdom
| | - Andrew J M Boulton
- Faculty of Medical and Human Sciences, University of Manchester, Manchester, United Kingdom; Diabetes Research Institute, University of Miami, Miami, FL, USA
| | - Neil D Reeves
- Research Centre for Musculoskeletal Science and Sports Medicine, Department of Life Sciences, Faculty of Science & Engineering, Manchester Metropolitan University, Oxford Road, Manchester, United Kingdom
| |
Collapse
|
|
16
|
Gonzalo-Skok O, Tous-Fajardo J, Moras G, Arjol-Serrano JL, Mendez-Villanueva A. A Repeated Power Training Enhances Fatigue Resistance While Reducing Intraset Fluctuations. J Strength Cond Res 2019; 33:2711-2721. [DOI: 10.1519/jsc.0000000000002541] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
|
|
17
|
Wu R, Delahunt E, Ditroilo M, Lowery MM, Segurado R, De Vito G. Changes in knee joint angle affect torque steadiness differently in young and older individuals. J Electromyogr Kinesiol 2019; 47:49-56. [DOI: 10.1016/j.jelekin.2019.05.010] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2019] [Revised: 05/13/2019] [Accepted: 05/13/2019] [Indexed: 12/01/2022] Open
|
|
18
|
Simoneau-Buessinger É, Jakobi JM, Toumi A, Mathys A, Bassement J, Barbier F, Leteneur S. Does Unilateral Lower Limb Amputation Influence Ankle Joint Torque in the Intact Leg? Arch Phys Med Rehabil 2019; 100:1259-1266. [DOI: 10.1016/j.apmr.2018.12.023] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2018] [Revised: 12/05/2018] [Accepted: 12/12/2018] [Indexed: 01/11/2023]
|
|
19
|
Fiogbé E, Carnavale BF, Takahashi ACDM. Exercise training in older adults, what effects on muscle force control? A systematic review of randomized clinical trials. Arch Gerontol Geriatr 2019; 83:138-150. [PMID: 31026723 DOI: 10.1016/j.archger.2019.04.005] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2018] [Revised: 04/02/2019] [Accepted: 04/09/2019] [Indexed: 12/17/2022]
Abstract
AIM To determine the magnitude of the effects of different exercise training (ET) modalities on variables of muscle force control in older adults. METHODS Relevant articles were searched in PubMed, Web of Science, Science Direct and Scopus, using the keywords: Aged AND "Exercise Movement Techniques" AND ("Complexity of torque" OR "Complexity of force" OR "Variability of torque" OR "Variability of force" OR "Force Steadiness" OR "Force fluctuations"). To be included in the full analysis, the studies had to be randomized controlled trials in which older adults were submitted to ET programs and muscle force control assessment. RESULTS The searches resulted in 702 articles from which 6 met all the inclusion criteria. The trials involved 171 healthy and functionally limited older adults (71.64 ± 1.53 years). Studies included resistance, steadiness and functional training programs. Training sessions were 2-3 time per week, lasted 6-16 months with intensities determined as percentage of the one repetition maximum loads. There is a heterogeneity regarding experimental set-up and data analysis parameters between studies. The findings show an improved muscle force control in older adults after ET. Such response is better evidenced by the assessment of the coefficient of variation (CV) of the force signals. There is moderate evidence that resistance training programs are effective to decrease CV of knee extensor force signals at lower force targets. CONCLUSIONS The findings from this review suggest that ET programs are effective to improve muscle force control in older adults.
Collapse
Affiliation(s)
- Elie Fiogbé
- Department of Physiotherapy, Federal University of Sao Carlos, Rodovia Washington Luiz, km 235, São Carlos, SP, CEP: 13565-905, Brazil.
| | | | | |
Collapse
|
|
20
|
Pereira HM, Schlinder-DeLap B, Keenan KG, Negro F, Farina D, Hyngstrom AS, Nielson KA, Hunter SK. Oscillations in neural drive and age-related reductions in force steadiness with a cognitive challenge. J Appl Physiol (1985) 2019; 126:1056-1065. [PMID: 30817244 DOI: 10.1152/japplphysiol.00821.2018] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
A cognitive challenge when imposed during a low-force isometric contraction will exacerbate sex- and age-related decreases in force steadiness, but the mechanism is not known. We determined the role of oscillations in the common synaptic input to motor units on force steadiness during a muscle contraction with a concurrent cognitive challenge. Forty-nine young adults (19-30 yr; 25 women, 24 men) and 36 old adults (60-85 yr; 19 women, 17 men) performed a cognitive challenge (counting backward by 13) during an isometric elbow flexion task at 5% of maximal voluntary contraction. Single-motor units were decomposed from high-density surface EMG recordings. For a subgroup of participants, motor units were matched during control and cognitive challenge trials, so the same motor unit was analyzed across conditions. Reduced force steadiness was associated with greater oscillations in the synaptic input to motor units during both control and cognitive challenge trials ( r = 0.45-0.47, P < 0.01). Old adults and young women showed greater oscillations in the common synaptic input to motor units and decreased force steadiness when the cognitive challenge was imposed, but young men showed no change across conditions (session × age × sex, P < 0.05). Oscillations in the common synaptic input to motor units is a potential mechanism for altered force steadiness when a cognitive challenge is imposed during low-force contractions in young women and old adults. NEW & NOTEWORTHY We found that oscillations in the common synaptic input to motor units were associated with a reduction in force steadiness when a cognitive challenge was imposed during low-force contractions of the elbow flexor muscles in young women and old men and women but not young men. Age- and sex-related muscle weakness was associated with these changes.
Collapse
Affiliation(s)
- Hugo M Pereira
- Department of Health and Exercise Science, University of Oklahoma , Norman, Oklahoma
| | | | - Kevin G Keenan
- Department of Kinesiology, University of Wisconsin-Milwaukee , Milwaukee, Wisconsin
| | - Francesco Negro
- Department of Clinical and Experimental Sciences, Università degli Studi di Brescia , Brescia , Italy
| | - Dario Farina
- Department of Bioengineering, Imperial College London, Royal School of Mines , London , United Kingdom
| | | | - Kristy A Nielson
- Department of Psychology, Marquette University , Milwaukee, Wisconsin
| | - Sandra K Hunter
- Department of Physical Therapy, Marquette University , Milwaukee, Wisconsin
| |
Collapse
|
|
21
|
Enoka RM, Duchateau J. Rate Coding and the Control of Muscle Force. Cold Spring Harb Perspect Med 2017; 7:cshperspect.a029702. [PMID: 28348173 DOI: 10.1101/cshperspect.a029702] [Citation(s) in RCA: 104] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
The force exerted by a muscle during a voluntary contraction depends on the number of motor units recruited for the action and the rates at which they discharge action potentials (rate coding). Over most of the operating range of a muscle, the nervous system controls muscle force by varying both motor unit recruitment and rate coding. Except at relatively low forces, however, the control of muscle force depends primarily on rate coding, especially during fast contractions. This review provides five examples of how the modulation of rate coding influences the force exerted by muscle during voluntary actions. The five examples comprise fast contractions, lengthening and shortening contractions, steady isometric contractions, fatiguing contractions, and contractions performed after a change in the daily level of physical activity.
Collapse
Affiliation(s)
- Roger M Enoka
- Department of Integrative Physiology, University of Colorado, Boulder, Colorado 80309-0354
| | - Jacques Duchateau
- Laboratory of Applied Biology and Neurophysiology, Neuroscience Institute, Université Libre de Bruxelles, 1070 Brussels, Belgium
| |
Collapse
|
|
22
|
Doucet BM, Mettler JA, Griffin L, Spirduso W. Force Irregularity Following Maximal Effort: The After-Peak Reduction. Percept Mot Skills 2016; 123:244-57. [PMID: 27502241 DOI: 10.1177/0031512516661274] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Irregularities in force output are present throughout human movement and can impair task performance. We investigated the presence of a large force discontinuity (after-peak reduction, APR) that appeared immediately following peak in maximal effort ramp contractions performed with the thumb adductor and ankle dorsiflexor muscles in 25 young adult participants (76% males, 24% females; M age 24.4 years, SD = 7.1). The after-peak reduction displayed similar parameters in both muscle groups with comparable drops in force during the after-peak reduction minima (thumb adductor: 27.5 ± 7.5% maximal voluntary contraction; ankle dorsiflexor: 25.8 ± 6.2% maximal voluntary contraction). A trend for the presence of fewer after-peak reductions with successive ramp trials was observed, suggesting a learning effect. Further investigation should explore underlying neural mechanisms contributing to the after-peak reduction.
Collapse
Affiliation(s)
- Barbara M Doucet
- Department of Occupational Therapy, Louisiana State University Health Sciences Center, New Orleans, LA, USA
| | - Joni A Mettler
- Department of Health and Human Performance, Texas State University, San Marcos, TX, USA
| | - Lisa Griffin
- Department of Kinesiology and Health Education, University of Texas at Austin, Austin, TX, USA
| | - Waneen Spirduso
- Department of Kinesiology and Health Education, University of Texas at Austin, Austin, TX, USA
| |
Collapse
|
|
23
|
Paoli A, Pacelli QF, Cancellara P, Toniolo L, Moro T, Canato M, Miotti D, Neri M, Morra A, Quadrelli M, Reggiani C. Protein Supplementation Does Not Further Increase Latissimus Dorsi Muscle Fiber Hypertrophy after Eight Weeks of Resistance Training in Novice Subjects, but Partially Counteracts the Fast-to-Slow Muscle Fiber Transition. Nutrients 2016; 8:nu8060331. [PMID: 27258300 PMCID: PMC4924172 DOI: 10.3390/nu8060331] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2016] [Revised: 05/16/2016] [Accepted: 05/19/2016] [Indexed: 11/18/2022] Open
Abstract
The response to resistance training and protein supplementation in the latissimus dorsi muscle (LDM) has never been investigated. We investigated the effects of resistance training (RT) and protein supplementation on muscle mass, strength, and fiber characteristics of the LDM. Eighteen healthy young subjects were randomly assigned to a progressive eight-week RT program with a normal protein diet (NP) or high protein diet (HP) (NP 0.85 vs. HP 1.8 g of protein·kg−1·day−1). One repetition maximum tests, magnetic resonance imaging for cross-sectional muscle area (CSA), body composition, and single muscle fibers mechanical and phenotype characteristics were measured. RT induced a significant gain in strength (+17%, p < 0.0001), whole muscle CSA (p = 0.024), and single muscle fibers CSA (p < 0.05) of LDM in all subjects. Fiber isometric force increased in proportion to CSA (+22%, p < 0.005) and thus no change in specific tension occurred. A significant transition from 2X to 2A myosin expression was induced by training. The protein supplementation showed no significant effects on all measured outcomes except for a smaller reduction of 2X myosin expression. Our results suggest that in LDM protein supplementation does not further enhance RT-induced muscle fiber hypertrophy nor influence mechanic muscle fiber characteristics but partially counteracts the fast-to-slow fiber shift.
Collapse
Affiliation(s)
- Antonio Paoli
- Department of Biomedical Sciences, University of Padova, Padova 35131, Italy.
| | - Quirico F Pacelli
- Department of Biomedical Sciences, University of Padova, Padova 35131, Italy.
| | - Pasqua Cancellara
- Department of Biomedical Sciences, University of Padova, Padova 35131, Italy.
| | - Luana Toniolo
- Department of Biomedical Sciences, University of Padova, Padova 35131, Italy.
| | - Tatiana Moro
- Department of Biomedical Sciences, University of Padova, Padova 35131, Italy.
| | - Marta Canato
- Department of Biomedical Sciences, University of Padova, Padova 35131, Italy.
| | | | - Marco Neri
- AIFeM (Italian Medicine and Fitness Federation), Ravenna 48121, Italy.
| | - Aldo Morra
- Euganea Medica, Diagnostic Centre, Via Colombo 13, Albignasego (Padova) 35020, Italy.
| | - Marco Quadrelli
- Euganea Medica, Diagnostic Centre, Via Colombo 13, Albignasego (Padova) 35020, Italy.
| | - Carlo Reggiani
- Department of Biomedical Sciences, University of Padova, Padova 35131, Italy.
| |
Collapse
|
|
24
|
Chung-Hoon K, Tracy BL, Dibble LE, Marcus RL, Burgess P, LaStayo PC. The Association Between Knee Extensor Force Steadiness, Force Accuracy, and Mobility in Older Adults Who Have Fallen. J Geriatr Phys Ther 2016; 39:1-7. [PMID: 25695470 PMCID: PMC4540703 DOI: 10.1519/jpt.0000000000000044] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
BACKGROUND Older adults often experience limited mobility, lower extremity muscle weakness, and increased fall risk. Furthermore, when older adults perform tasks that require control of submaximal force, impairments in their ability to maintain steady and accurate force output have been reported. Such problems may be related to deteriorating levels of mobility, particularly in older adults who have fallen. PURPOSE The purpose of this study was to determine whether an association exists between muscle force steadiness (MFS) or muscle force accuracy (MFA) of the knee extensors and mobility in older adults who have fallen. METHODS Twenty older adults ((Equation is included in full-text article.)= 77.5 ± 7 years, 5 males and 15 females) with 2 or more comorbid conditions and who experienced a fall in the past year underwent assessment of maximal voluntary isometric contraction of the knee extensors. A submaximal target force of 50% of their maximal voluntary isometric contraction was used to determine concentric and eccentric (ECC) steadiness (the fluctuations in force production) and accuracy (the average distance of the mean force from the target force) measures. Mobility was indicated by the 6-minute walk test, the Timed Up and Go, stair ascent, and stair descent tests. Correlation analysis was used to assess the relationship between measures of muscle force control and mobility. RESULTS The correlations between muscle force steadiness and mobility were not significant (P > .05) for either contraction type. However, MFA during ECC contractions only was correlated significantly with all measures of mobility-6 minute walk test (r = -0.48; P = .03), Timed Up and Go (r = 0.68; P = .01), stair ascent (r = 0.60; P = .01), and stair descent (r = 0.75; P < .01). CONCLUSION The identification of the relationship between ECC MFA and mobility in older adults who have fallen is novel. Although the correlations are not causal, these relationships suggest that inaccurate force output during ECC contractions of the knee extensors is linked to impaired mobility.
Collapse
Affiliation(s)
- Kaiwi Chung-Hoon
- University of Utah, Department of Physical Therapy, 520 Wakara Way, SLC, UT 84108
| | - Brian L. Tracy
- Colorado State University, Department of Health and Exercise Science, 220 Moby-B Complex, Fort Collins, CO 80523
| | - Leland E. Dibble
- University of Utah, Department of Physical Therapy, 520 Wakara Way, SLC, UT 84108
| | - Robin L. Marcus
- University of Utah, Department of Physical Therapy, 520 Wakara Way, SLC, UT 84108
| | - Paul Burgess
- University of Utah, Department of Physical Therapy, 520 Wakara Way, SLC, UT 84108
| | - Paul C. LaStayo
- University of Utah, Department of Physical Therapy, 520 Wakara Way, SLC, UT 84108
| |
Collapse
|
|
25
|
Borde R, Hortobágyi T, Granacher U. Dose-Response Relationships of Resistance Training in Healthy Old Adults: A Systematic Review and Meta-Analysis. Sports Med 2015; 45:1693-720. [PMID: 26420238 PMCID: PMC4656698 DOI: 10.1007/s40279-015-0385-9] [Citation(s) in RCA: 438] [Impact Index Per Article: 43.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
BACKGROUND Resistance training (RT) is an intervention frequently used to improve muscle strength and morphology in old age. However, evidence-based, dose-response relationships regarding specific RT variables (e.g., training period, frequency, intensity, volume) are unclear in healthy old adults. OBJECTIVES The aims of this systematic review and meta-analysis were to determine the general effects of RT on measures of muscle strength and morphology and to provide dose-response relationships of RT variables through an analysis of randomized controlled trials (RCTs) that could improve muscle strength and morphology in healthy old adults. DATA SOURCES A computerized, systematic literature search was performed in the electronic databases PubMed, Web of Science, and The Cochrane Library from January 1984 up to June 2015 to identify all RCTs related to RT in healthy old adults. STUDY ELIGIBILITY CRITERIA The initial search identified 506 studies, with a final yield of 25 studies. Only RCTs that examined the effects of RT in adults with a mean age of 65 and older were included. The 25 studies quantified at least one measure of muscle strength or morphology and sufficiently described training variables (e.g., training period, frequency, volume, intensity). STUDY APPRAISAL AND SYNTHESIS METHODS We quantified the overall effects of RT on measures of muscle strength and morphology by computing weighted between-subject standardized mean differences (SMDbs) between intervention and control groups. We analyzed the data for the main outcomes of one-repetition maximum (1RM), maximum voluntary contraction under isometric conditions (MVC), and muscle morphology (i.e., cross-sectional area or volume or thickness of muscles) and assessed the methodological study quality by Physiotherapy Evidence Database (PEDro) scale. Heterogeneity between studies was assessed using I2 and χ2 statistics. A random effects meta-regression was calculated to explain the influence of key training variables on the effectiveness of RT in terms of muscle strength and morphology. For meta-regression, training variables were divided into the following subcategories: volume, intensity, and rest. In addition to meta-regression, dose-response relationships were calculated independently for single training variables (e.g., training frequency). RESULTS RT improved muscle strength substantially (mean SMDbs = 1.57; 25 studies), but had small effects on measures of muscle morphology (mean SMDbs = 0.42; nine studies). Specifically, RT produced large effects in both 1RM of upper (mean SMDbs = 1.61; 11 studies) and lower (mean SMDbs = 1.76; 19 studies) extremities and a medium effect in MVC of lower (mean SMDbs = 0.76; four studies) extremities. Results of the meta-regression revealed that the variables "training period" (p = 0.04) and "intensity" (p < 0.01) as well as "total time under tension" (p < 0.01) had significant effects on muscle strength, with the largest effect sizes for the longest training periods (mean SMDbs = 2.34; 50-53 weeks), intensities of 70-79% of the 1RM (mean SMDbs = 1.89), and total time under tension of 6.0 s (mean SMDbs = 3.61). A tendency towards significance was found for rest in between sets (p = 0.06), with 60 s showing the largest effect on muscle strength (mean SMDbs = 4.68; two studies). We also determined the independent effects of the remaining training variables on muscle strength. The following independently computed training variables are most effective in improving measures of muscle strength: a training frequency of two sessions per week (mean SMDbs = 2.13), a training volume of two to three sets per exercise (mean SMDbs = 2.99), seven to nine repetitions per set (mean SMDbs = 1.98), and a rest of 4.0 s between repetitions (SMDbs = 3.72). With regard to measures of muscle morphology, the small number of identified studies allowed us to calculate meta-regression for the subcategory training volume only. No single training volume variable significantly predicted RT effects on measures of muscle morphology. Additional training variables were independently computed to detect the largest effect for the single training variable. A training period of 50-53 weeks, a training frequency of three sessions per week, a training volume of two to three sets per exercise, seven to nine repetitions per set, a training intensity from 51 to 69% of the 1RM, a total time under tension of 6.0 s, a rest of 120 s between sets, and a rest of 2.5 s between repetitions turned out to be most effective. LIMITATIONS The current results must be interpreted with caution because of the poor overall methodological study quality (mean PEDro score 4.6 points) and the considerable large heterogeneity (I2) = 80%, χ2 = 163.1, df = 32, p < 0.01) for muscle strength. In terms of muscle morphology, our search identified nine studies only, which is why we consider our findings preliminary. While we were able to determine a dose-response relationship based on specific individual training variables with respect to muscle strength and morphology, it was not possible to ascertain any potential interactions between these variables. We recognize the limitation that the results may not represent one general dose-response relationship. CONCLUSIONS This systematic literature review and meta-analysis confirmed the effectiveness of RT on specific measures of upper and lower extremity muscle strength and muscle morphology in healthy old adults. In addition, we were able to extract dose-response relationships for key training variables (i.e., volume, intensity, rest), informing clinicians and practitioners to design effective RTs for muscle strength and morphology. Training period, intensity, time under tension, and rest in between sets play an important role in improving muscle strength and morphology and should be implemented in exercise training programs targeting healthy old adults. Still, further research is needed to reveal optimal dose-response relationships following RT in healthy as well as mobility limited and/or frail old adults.
Collapse
Affiliation(s)
- Ron Borde
- Division of Training and Movement Sciences, Research Focus Cognition Sciences, University of Potsdam, Am Neuen Palais 10, Building 12, 14469, Potsdam, Germany.
| | - Tibor Hortobágyi
- Center for Human Movement Sciences, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
- Faculty of Health and Life Sciences, Northumbria University, Newcastle Upon Tyne, UK
| | - Urs Granacher
- Division of Training and Movement Sciences, Research Focus Cognition Sciences, University of Potsdam, Am Neuen Palais 10, Building 12, 14469, Potsdam, Germany.
| |
Collapse
|
|
26
|
Rice DA, McNair PJ, Lewis GN, Mannion J. Experimental knee pain impairs submaximal force steadiness in isometric, eccentric, and concentric muscle actions. Arthritis Res Ther 2015; 17:259. [PMID: 26377678 PMCID: PMC4574021 DOI: 10.1186/s13075-015-0768-1] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2015] [Accepted: 08/26/2015] [Indexed: 11/10/2022] Open
Abstract
INTRODUCTION Populations with knee joint damage, including arthritis, have noted impairments in the regulation of submaximal muscle force. It is difficult to determine the exact cause of such impairments given the joint pathology and associated neuromuscular adaptations. Experimental pain models that have been used to isolate the effects of pain on muscle force regulation have shown impaired force steadiness during acute pain. However, few studies have examined force regulation during dynamic contractions, and these findings have been inconsistent. The goal of the current study was to examine the effect of experimental knee joint pain on submaximal quadriceps force regulation during isometric and dynamic contractions. METHODS The study involved fifteen healthy participants. Participants were seated in an isokinetic dynamometer. Knee extensor force matching tasks were completed in isometric, eccentric, and concentric muscle contraction conditions. The target force was set to 10 % of maximum for each contraction type. Hypertonic saline was then injected into the infrapatella fat pad to generate acute joint pain. The force matching tasks were repeated during pain and once more 5 min after pain had subsided. RESULTS Hypertonic saline resulted in knee pain with an average peak pain rating of 5.5 ± 2.1 (0-10 scale) that lasted for 18 ± 4 mins. Force steadiness significantly reduced during pain across all three muscle contraction conditions. There was a trend to increased force matching error during pain but this was not significant. CONCLUSION Experimental knee pain leads to impaired quadriceps force steadiness during isometric, eccentric, and concentric contractions, providing further evidence that joint pain directly affects motor performance. Given the established relationship between submaximal muscle force steadiness and function, such an effect may be detrimental to the performance of tasks in daily life. In order to restore motor performance in people with painful arthritic conditions of the knee, it may be important to first manage their pain more effectively.
Collapse
Affiliation(s)
- David A Rice
- Health and Rehabilitation Research Institute, Auckland University of Technology, Private Bag 92006, Auckland, 1142, New Zealand. .,Waitemata Pain Service, Department of Anaesthesia and Perioperative Medicine, North Shore Hospital, Private Bag 93-503, Takapuna, Auckland, New Zealand.
| | - Peter J McNair
- Health and Rehabilitation Research Institute, Auckland University of Technology, Private Bag 92006, Auckland, 1142, New Zealand.
| | - Gwyn N Lewis
- Health and Rehabilitation Research Institute, Auckland University of Technology, Private Bag 92006, Auckland, 1142, New Zealand.
| | - Jamie Mannion
- Unitec Institute of Technology, Private Bag 92025, Victoria St West, Auckland, New Zealand.
| |
Collapse
|
|
27
|
Abstract
INTRODUCTION The purpose was to determine the effect of peripheral neuropathy (PN) on motor output variability for ankle muscles of older adults, and the relation between ankle motor variability and postural stability in PN patients. METHODS Older adults with (O-PN) and without PN (O), and young adults (Y) underwent assessment of standing postural stability and ankle muscle force steadiness. RESULTS O-PN displayed impaired ankle muscle force control and postural stability compared with O and Y groups. For O-PN, the amplitude of plantarflexor force fluctuations was moderately correlated with postural stability under no-vision conditions (r = .54, p = .01). DISCUSSION The correlation of variations in ankle force with postural stability in PN suggests a contribution of ankle muscle dyscontrol to the postural instability that impacts physical function for older adults with PN.
Collapse
|
|
28
|
Kavanagh JJ, Wedderburn-Bisshop J, Keogh JWL. Resistance Training Reduces Force Tremor and Improves Manual Dexterity in Older Individuals With Essential Tremor. J Mot Behav 2015; 48:20-30. [PMID: 25923582 DOI: 10.1080/00222895.2015.1028583] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
Although symptoms of Essential Tremor (ET) are typically controlled with medication, it is of interest to explore additional therapies to assist with functionality. The purpose of this study was to determine if a generalized upper limb resistance training (RT) program improves manual dexterity and reduces force tremor in older individuals with ET. Ten Essential Tremor and 9 controls were recruited into a dual group, pretest-posttest intervention study. Participants performed 6 weeks of upper-limb RT, and battery of manual dexterity and isometric force tremor assessments were performed before and after the RT to determine the benefits of the program. The six-week, high-load, RT program produced strength increases in each limb for the ET and healthy older group. These changes in strength aligned with improvements in manual dexterity and tremor-most notably for the ET group. The least affected limb and the most affected limb exhibited similar improvements in functional assessments of manual dexterity, whereas reductions in force tremor amplitude following the RT program were restricted to the most affected limb of the ET group. These findings suggest that generalized upper limb RT program has the potential to improve aspects of manual dexterity and reduce force tremor in older ET patients.
Collapse
Affiliation(s)
- Justin J Kavanagh
- a Centre for Musculoskeletal Research , Griffith University , Gold Coast , Australia
| | | | - Justin W L Keogh
- b Faculty of Health Sciences and Medicine , Bond University , Gold Coast , Australia
| |
Collapse
|
|
29
|
Mohamed RA, Sherief AEAA. Bicycle ergometer versus treadmill on balance and gait parameters in children with hemophilia. EGYPTIAN JOURNAL OF MEDICAL HUMAN GENETICS 2015. [DOI: 10.1016/j.ejmhg.2014.11.001] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022] Open
|
|
30
|
Chung-Hoon K, Tracy BL, Marcus R, Dibble L, Burgess P, Lastayo PC. Effects of practice on variability of muscle force. Percept Mot Skills 2015; 120:475-90. [PMID: 25799026 DOI: 10.2466/26.pms.120v12x4] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
The motor skill required to decrease the variability in muscle force steadiness can be challenging. The purposes of this study were to determine whether muscle force steadiness improved following repeated trials and whether the number of trials varied for healthy younger adults, healthy older adults, and older adults who have fallen to obtain stable muscle force steadiness measures. Sixty participants performed 30 concentric and eccentric contractions of the knee extensors on an isokinetic dynamometer. Each group had significant improvements in muscle force steadiness and obtained stable measures within six to nine trials. Healthy younger and older adults, and older adults who have fallen, can improve muscle force steadiness. These findings provide a framework for methodological approaches when testing steadiness in varying populations.
Collapse
|
|
31
|
Brunner A, Stäuber F, Göhler S, Czepa D, Wendel M, Seuser A, Hilberg T. Impact of joint status on contraction steadiness of m. quadriceps femoris in people with severe haemophilia. Haemophilia 2014; 20:884-90. [DOI: 10.1111/hae.12493] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/06/2014] [Indexed: 12/19/2022]
Affiliation(s)
- A. Brunner
- Department of Sports Medicine; University of Wuppertal; Wuppertal Germany
| | - F. Stäuber
- Department of Sports Medicine; University of Wuppertal; Wuppertal Germany
| | - S. Göhler
- Department of Sports Medicine; University of Wuppertal; Wuppertal Germany
| | - D. Czepa
- Department of Sports Medicine; University of Wuppertal; Wuppertal Germany
| | - M. Wendel
- Institute of Motion Analysis and Quality Control of the Locomotive System; Bonn Germany
| | - A. Seuser
- Institute of Motion Analysis and Quality Control of the Locomotive System; Bonn Germany
| | - T. Hilberg
- Department of Sports Medicine; University of Wuppertal; Wuppertal Germany
| |
Collapse
|
|
32
|
Smith JW, Marcus RL, Peters CL, Pelt CE, Tracy BL, LaStayo PC. Muscle force steadiness in older adults before and after total knee arthroplasty. J Arthroplasty 2014; 29:1143-8. [PMID: 24405624 DOI: 10.1016/j.arth.2013.11.023] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/02/2013] [Revised: 11/06/2013] [Accepted: 11/26/2013] [Indexed: 02/01/2023] Open
Abstract
The ability to control submaximal muscle forces has been shown to be associated with age-related decreases in physical function, such as increased tendency to fall. This study compared quadriceps muscle force steadiness (MFS) in individuals with knee OA before and after total knee arthroplasty (TKA) to an age-matched group of controls. Lower extremity MFS was measured in 13 subjects with knee OA before and at six months after TKA (TKA-GROUP) and compared to an age-matched control group (CONTROL-GROUP). MFS was significantly more impaired in the TKA-GROUP at the pre-operative, but not post-operative visit, and significantly improved between the pre-operative and post-operative visits. Further research is warranted to evaluate the relation between this MFS measurement and physical functional performance in those at high risk for falling.
Collapse
Affiliation(s)
- Jessica W Smith
- Department of Bioengineering, University of Utah; Department of Physical Therapy, University of Utah
| | | | | | - Christopher E Pelt
- Department of Orthopedics and University Orthopedics Center, University of Utah
| | - Brian L Tracy
- Department of Health and Exercise Science, Colorado State University
| | - Paul C LaStayo
- Department of Bioengineering, University of Utah; Department of Physical Therapy, University of Utah; Department of Orthopedics and University Orthopedics Center, University of Utah; Department of Exercise Science, University of Utah
| |
Collapse
|
|
33
|
Smith JW, Christensen JC, Marcus RL, LaStayo PC. Muscle force and movement variability before and after total knee arthroplasty: A review. World J Orthop 2014; 5:69-79. [PMID: 24829868 PMCID: PMC4017309 DOI: 10.5312/wjo.v5.i2.69] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/29/2013] [Revised: 02/26/2014] [Accepted: 03/11/2014] [Indexed: 02/06/2023] Open
Abstract
Variability in muscle force output and movement variability are important aspects of identifying individuals with mobility deficits, central nervous system impairments, and future risk of falling. This has been investigated in elderly healthy and impaired adults, as well as in adults with osteoarthritis (OA), but the question of whether the same correlations also apply to those who have undergone a surgical intervention such as total knee arthroplasty (TKA) is still being investigated. While there is a growing body of literature identifying potential rehabilitation targets for individuals who have undergone TKA, it is important to first understand the underlying post-operative impairments to more efficiently target functional deficits that may lead to improved long-term outcomes. The purpose of this article is to review the potential role of muscle force output and movement variability in TKA recipients. The narrative review relies on existing literature in elderly healthy and impaired individuals, as well as in those with OA before and following TKA. The variables that may predict long-term functional abilities and deficits are discussed in the context of existing literature in healthy older adults and older adults with OA and following TKA, as well as the role future research in this field may play in providing evidence-based data for improved rehabilitation targets.
Collapse
|
|
34
|
Justice JN, Mani D, Pierpoint LA, Enoka RM. Fatigability of the dorsiflexors and associations among multiple domains of motor function in young and old adults. Exp Gerontol 2014; 55:92-101. [PMID: 24703888 DOI: 10.1016/j.exger.2014.03.018] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2013] [Revised: 02/22/2014] [Accepted: 03/24/2014] [Indexed: 10/25/2022]
Abstract
Declines in neuromuscular function, including measures of mobility, muscle strength, steadiness, and patterns of muscle activation, accompany advancing age and are often associated with reduced quality of life and mortality. Paradoxically, older adults are less fatigable than young adults in some tasks. The purpose of this study was to determine the influence of age on fatigability of the dorsiflexors and to evaluate the ecological validity of this test by comparing it to motor function subdomains known to decline with advancing age. The community-dwelling older adults (n=52, 75.2±6.0years) were more fatigable than young adults (n=26, 22.2±3.7years), as assessed by endurance time for supporting a submaximal load (20% of one-repetition maximum; 1-RM) with an isometric contraction of the dorsiflexor muscles (8.9±0.6min and 15.5±0.9min, p<0.001), including participants matched for 1-RM load and sex (Y: 13.3±4.0min, O: 8.5±6.1min, n=11 pairs, 6 women, p<0.05). When the older adults were separated into two groups (65-75 and 76-90years), however, only endurance time for the oldest group was less than that for the other two groups (p<0.01). All measures of motor function were significantly correlated (all p<0.05) with dorsiflexor endurance time for the older adults, and multiple regression analysis revealed that the variance in endurance time was most closely associated with age, steadiness, and knee flexor strength (R(2)=0.50, p<0.001). These findings indicate that dorsiflexor fatigability provides a valid biomarker of motor function in older adults.
Collapse
Affiliation(s)
- Jamie N Justice
- Department of Integrative Physiology, University of Colorado Boulder, 354 UCB CO, 80309-0354, USA.
| | - Diba Mani
- Department of Integrative Physiology, University of Colorado Boulder, 354 UCB CO, 80309-0354, USA.
| | - Lauren A Pierpoint
- Department of Integrative Physiology, University of Colorado Boulder, 354 UCB CO, 80309-0354, USA.
| | - Roger M Enoka
- Department of Integrative Physiology, University of Colorado Boulder, 354 UCB CO, 80309-0354, USA.
| |
Collapse
|
|
35
|
Parikh PJ, Cole KJ. Effects of transcranial direct current stimulation in combination with motor practice on dexterous grasping and manipulation in healthy older adults. Physiol Rep 2014; 2:e00255. [PMID: 24760509 PMCID: PMC4002235 DOI: 10.1002/phy2.255] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
Abstract Transcranial anodal stimulation (tDCS) over primary motor cortex (M1) improves dexterous manipulation in healthy older adults. However, the beneficial effects of anodal tDCS in combination with motor practice on natural and clinically relevant functional manual tasks, and the associated changes in the digit contact forces are not known. To this end, we studied the effects of 20 min of tDCS applied over M1 for the dominant hand combined with motor practice (MP) in a sham-controlled crossover study. We monitored the forces applied to an object that healthy elderly individuals grasped and manipulated, and their performances on the Grooved Pegboard Test and the Key-slot task. Practice improved performance on the Pegboard test, and anodal tDCS + MP improved retention of this performance gain when tested 35 min later, whereas similar performance gains degraded in the sham group after 35 min. Interestingly, grip force variability on an isometric precision grip task performed with visual feedback of precision force increased following anodal tDCS + MP, but not sham tDCS + MP. This finding suggests that anodal tDCS over M1 might alter the descending drive to spinal motor neurons involved in the performance of isometric precision grip task under visual feedback leading to increased fluctuations in the grip force exerted on the object. Our results demonstrate that anodal stimulation in combination with motor practice helps older adults to retain their improved performance on a functionally relevant manual task in healthy older adults.
Collapse
Affiliation(s)
- Pranav J Parikh
- Motor Control Laboratories, Department of Health and Human Physiology, University of Iowa, Iowa City, 52242, Iowa
| | | |
Collapse
|
|
36
|
Gyorkos AM, Spitsbergen JM. GDNF content and NMJ morphology are altered in recruited muscles following high-speed and resistance wheel training. Physiol Rep 2014; 2:e00235. [PMID: 24744904 PMCID: PMC3966253 DOI: 10.1002/phy2.235] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2014] [Revised: 01/20/2014] [Accepted: 01/21/2014] [Indexed: 12/25/2022] Open
Abstract
Glial cell line‐derived neurotrophic factor (GDNF) may play a role in delaying the onset of aging and help compress morbidity by preventing motor unit degeneration. Exercise has been shown to alter GDNF expression differently in slow‐ and fast‐twitch myofibers. The aim was to examine the effects of different intensities (10, 20, ~30, and ~40 m·min−1) of wheel running on GDNF expression and neuromuscular junction (NMJ) plasticity in slow‐ and fast‐twitch myofibers. Male Sprague‐Dawley Rats (4 weeks old) were divided into two sedentary control groups (CON4 week, n = 5 and CON6 week, n = 5), two involuntary running groups, one at a low velocity; 10 m/min (INVOL‐low, n = 5), and one at a higher velocity; 20 m/min (INVOL‐high, n = 5), and two voluntary running groups with resistance (VOL‐R, n = 5, 120 g), and without resistance (VOL‐NR, n = 5, 4.5 g). GDNF protein content, determined by enzyme‐linked immunosorbent assay (ELISA), increased significantly in the recruited muscles. Plantaris (PLA) GDNF protein content increased 174% (P <0.05) and 161% (P <0.05) and end plate‐stained area increased 123% (P <0.05) and 72% (P <0.05) following VOL‐R, and VOL‐NR training, respectively, when compared to age‐matched controls. A relationship exists between GDNF protein content and end plate area (r = 0.880, P < 0.01, n = 15). VOL‐R training also resulted in more dispersed synapses in the PLA muscle when compared to age‐matched controls (P <0.05). Higher intensity exercise (>30 m/min) can increase GDNF protein content in fast‐twitch myofibers as well as induce changes in the NMJ morphology. These findings help to inform exercise prescription to preserve the integrity of the neuromuscular system through aging and disease. Higher intensity exercise (>30 m/min) can increase glial cell line‐derived neurotrophic factor (GDNF) protein content in fast‐twitch myofibers as well as induce changes in the neuromuscular junction (NMJ) morphology. These findings help to inform exercise prescription to preserve the integrity of the neuromuscular system through aging and disease.
Collapse
Affiliation(s)
- Amy Morrison Gyorkos
- Department of Biological Sciences, Western Michigan University, 1903 W Michigan Ave., Kalamazoo, 49008-5410, Michigan
| | - John M Spitsbergen
- Department of Biological Sciences, Western Michigan University, 1903 W Michigan Ave., Kalamazoo, 49008-5410, Michigan
| |
Collapse
|
|
37
|
Durbaba R, Cassidy A, Budini F, Macaluso A. The effects of isometric resistance training on stretch reflex induced tremor in the knee extensor muscles. J Appl Physiol (1985) 2013; 114:1647-56. [PMID: 23580599 DOI: 10.1152/japplphysiol.00917.2011] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
This study examines the effect of 4 wk of high-intensity isometric resistance training on induced tremor in knee extensor muscles. Fourteen healthy volunteers were assigned to either the training group (n = 7) or the nontraining control group (n = 7). Induced tremor was assessed by measuring force fluctuations during anisometric contractions against spring loading, whose compliance was varied to allow for preferential activation of the short or long latency stretch reflex components. Effects of high-intensity isometric resistance training on induced tremor was assessed under two contraction conditions: relative force matching, where the relative level of activity was equal for both pre- and post-training sessions, set at 30% maximum voluntary contraction (MVC), and absolute force matching, where the level of activity was set to 30% pretrained MVC. The training group experienced a 26.5% increase in MVC in contrast to the 0.8% for the control group. For relative force-matching contractions, induced tremor amplitude and frequency did not change in either the training or control group. During absolute force-matching contractions, induced tremor amplitude was decreased by 37.5% and 31.6% for the short and long components, respectively, with no accompanying change in frequency, for the training group. No change in either measure was observed in the control group for absolute force-matching contractions. The results are consistent with high-intensity isometric resistance training induced neural changes leading to increased strength, coupled with realignment of stretch reflex automatic gain compensation to the new maximal force output. Also, previous reported reductions in anisometric tremor following strength training may partly be due to changed stretch reflex behavior.
Collapse
Affiliation(s)
- Rade Durbaba
- Department of Applied Sciences, Faculty of Health and Life Sciences, Northumbria University, Newcastle, United Kingdom.
| | | | | | | |
Collapse
|
|
38
|
Kobayashi H, Koyama Y, Enoka RM, Suzuki S. A unique form of light-load training improves steadiness and performance on some functional tasks in older adults. Scand J Med Sci Sports 2012; 24:98-110. [DOI: 10.1111/j.1600-0838.2012.01460.x] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/22/2012] [Indexed: 11/26/2022]
Affiliation(s)
- H. Kobayashi
- Graduate School of Human Sciences; Waseda University; Mikajima Tokorozawa Japan
| | - Y. Koyama
- Graduate School of Human Sciences; Waseda University; Mikajima Tokorozawa Japan
| | - R. M. Enoka
- Department of Integrative Physiology; University of Colorado; Boulder Colorado USA
| | - S. Suzuki
- Graduate School of Human Sciences; Waseda University; Mikajima Tokorozawa Japan
| |
Collapse
|
|
39
|
The motor-learning process of older adults in eccentric bicycle ergometer training. J Aging Phys Act 2011; 20:345-62. [PMID: 22186770 DOI: 10.1123/japa.20.3.345] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
This study describes the motor-learning process of older individuals during the course of a training intervention on a motor-driven eccentric bicycle ergometer. Seventeen women and 16 men (64 ± 6 yr) took part in a 10-wk training program. Uniformity of force production and consistency of timing were used to describe their motor performance. The results suggested that participants improved the coefficient of variation of peak force during the intervention (measured at the 2nd, 4th, 6th, 8th, 10th, 12th, and the 18th training sessions). They reached a fairly constant level of motor performance around the 12th training session (5 wk). Age and sex affected improvements in the early phases of the learning process to an extent, but the differences diminished by the end of the intervention. These results suggest that the force control of continuous eccentric muscle contractions improves as a result of training in older adults.
Collapse
|
|
40
|
Marmon AR, Gould JR, Enoka RM. Practicing a functional task improves steadiness with hand muscles in older adults. Med Sci Sports Exerc 2011; 43:1531-7. [PMID: 21266932 DOI: 10.1249/mss.0b013e3182100439] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
INTRODUCTION Improvements in steadiness with practice have been associated with enhanced performance on a functional task in old adults. PURPOSE The aims of the study were to examine the specificity of the association between steadiness and a functional task and to assess the influence of practicing a functional task on force steadiness of hand muscles. METHODS Twenty-three older adults (≥70 yr) participated in the study and were assigned to either a practice group (n = 15) or a control group (n = 8). Subjects completed two testing sessions that were 2 wk apart. The practice group completed six additional sessions to practice a functional task (Grooved Pegboard). Tests included maximal voluntary contractions (MVC), force steadiness (precision pinch and index finger abduction) at three target forces (5%, 15%, and 25% MVC), and the Grooved Pegboard test. The associations between strength, steadiness, and the time needed to complete the Grooved Pegboard test were examined. In addition, MVC force, steadiness, and pegboard time were compared between the two testing sessions. RESULTS The time needed to complete the Grooved Pegboard test was associated with index finger abduction steadiness for two of the three target forces (15% and 25% MVC) but was not associated with pinch steadiness. Practice significantly reduced the time needed to complete the Grooved Pegboard test and improved steadiness in both tasks. CONCLUSIONS Force steadiness provides an appropriate index of hand function, especially when measured at low forces.
Collapse
Affiliation(s)
- Adam R Marmon
- Department of Physical Therapy, University of Delaware, Newark, DE 19711, USA.
| | | | | |
Collapse
|
|
41
|
Chow JW, Stokic DS. Force control of quadriceps muscle is bilaterally impaired in subacute stroke. J Appl Physiol (1985) 2011; 111:1290-5. [DOI: 10.1152/japplphysiol.00462.2011] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
We tested the hypothesis that force variability and error during maintenance of submaximal isometric knee extension are greater in subacute stroke patients than in controls and are related to motor impairments. Contralesional (more-affected) and ipsilesional (less-affected) legs of 33 stroke patients with sufficiently high motor abilities (62 ± 13 yr, 16 ± 2 days postinjury) and the dominant leg of 20 controls (62 ± 10 yr) were tested in sitting position. After peak knee extension torque [maximum voluntary contraction (MVC)] was established, subjects maintained 10, 20, 30, and 50% of MVC as steady and accurate as possible for 10 s by matching voluntary force to the target level displayed on a monitor. Coefficient of variation (CV) and root-mean-square error (RMSE) were used to quantify force variability and error, respectively. The MVC was significantly smaller in the more-affected than less-affected leg, and both were significantly lower than in controls. The CV was significantly larger in the more-affected than less-affected leg at 20 and 50% MVC, whereas both were significantly larger compared with controls across all force levels. Both more-affected and less-affected legs of patients showed significantly greater RMSE than controls at 30 and 50% MVC. The CV and RMSE were not related to the Fugl-Meyer motor score or to the Rivermead Mobility Index. The CV negatively correlated with MVC in controls but only in the less-affected leg of patients. It is concluded that isometric knee extension strength and force control are bilaterally impaired soon after stroke but more so in the more-affected leg. Future studies should examine possible mechanisms and the evolution of these changes.
Collapse
Affiliation(s)
- John W. Chow
- Center for Neuroscience and Neurological Recovery, Methodist Rehabilitation Center, Jackson, Mississippi
| | - Dobrivoje S. Stokic
- Center for Neuroscience and Neurological Recovery, Methodist Rehabilitation Center, Jackson, Mississippi
| |
Collapse
|
|
42
|
Bezerra P, Zhou S, Crowley Z, Davie A, Baglin R. Effects of electromyostimulation on knee extensors and flexors strength and steadiness in older adults. J Mot Behav 2011; 43:413-21. [PMID: 21978241 DOI: 10.1080/00222895.2011.620039] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
It is known that electromyostimulation (EMS) alone or superimposed over voluntary contraction (EV) can effectively improve muscle strength. However, the effect of this type of training on the ability to control force production at submaximal levels is unknown. The authors examined the effects of EV training on steadiness in force production of knee extensors and flexors in older adults. Forty participants, including 20 men and 20 women, 60-77 years of age, were randomly allocated into a control group (CG) and an electromyostimulation superimposed over voluntary contraction (EVG) group. The EVG performed 30 bilateral isometric knee extension and flexion contractions per session, 3 training sessions per week, for 6 weeks. The variations in force production, expressed in absolute (standard deviation [SD]) and relative (coefficient of variation [CV]) terms, were assessed in isometric contractions at 5%, 15% and 25% maximal voluntary contraction (MVC) levels. Results indicated that MVC increased in knee extension and flexion in EVG (p < .05) after the training; steadiness CV also improved at 15% MVC in knee flexion (p < .05) but no significant changes were found in knee extension and steadiness SD. The training-induced changes in MVC were not correlated to steadiness CV that might indicate different mechanisms underlying these adaptations.
Collapse
Affiliation(s)
- Pedro Bezerra
- School of Health and Human Science, Southern Cross University, Lismore, Australia.
| | | | | | | | | |
Collapse
|
|
43
|
Marmon AR, Pascoe MA, Schwartz RS, Enoka RM. Associations among strength, steadiness, and hand function across the adult life span. Med Sci Sports Exerc 2011; 43:560-7. [PMID: 20689447 DOI: 10.1249/mss.0b013e3181f3f3ab] [Citation(s) in RCA: 93] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
INTRODUCTION Age-related differences in force steadiness have been extensively examined and used as an index of motor function. However, the functional relevance of steadiness remains unclear. PURPOSE The aim here was to evaluate the relations among hand strength, steadiness, and function across the adult life span. METHODS Seventy-five adults (45 women; 18-89 yr) performed three strength, two steadiness, and four functional tests with both hands. Strength was measured during index finger abduction, precision pinch, and handgrip, and steadiness was measured during index finger abduction and precision pinch. Functional tests included the Grooved Pegboard test, the game Operation™, a scissor task, and a tracing task. RESULTS Moderate correlations were observed between both steadiness tasks and performance on the Grooved Pegboard test (R(2) = 0.57 and R(2) = 0.46, respectively) and Operation™ (R(2) = -0.47 and R(2) = -0.57, respectively). CONCLUSIONS The relation between measures of steadiness and hand function suggests that the physiological mechanisms responsible for differences in steadiness also contribute to differences in the performance of fine motor tasks with the hand.
Collapse
Affiliation(s)
- Adam R Marmon
- Department of Physical Therapy, University of Delaware, Newark, DE 19711, USA.
| | | | | | | |
Collapse
|
|
44
|
Bryant AL, Clark RA, Pua YH. Morphology of hamstring torque-time curves following ACL injury and reconstruction: mechanisms and implications. J Orthop Res 2011; 29:907-14. [PMID: 21259335 DOI: 10.1002/jor.21306] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/15/2009] [Accepted: 10/12/2010] [Indexed: 02/04/2023]
Abstract
The purposes of this study were (i) to examine the effects of anterior cruciate ligament (ACL) status on hamstring force steadiness, peak hamstring strength, quadriceps (antagonist) activation, and physical performance, and (ii) to evaluate the associations of physical performance with hamstring steadiness and hamstring strength. Thirteen subjects with unilateral deficiency of the ACL (ACLD), 39 matched subjects with unilateral reconstructed ACL (ACLR; n = 25 with bone-patella tendon-bone (ACLR-PT) graft and n = 14 with combined semitendinosus and gracilis tendon (ACLR-STGT) graft) and 33 control subjects participated. Each subject performed maximal-effort isokinetic knee flexion repetitions at 180° s(-1) with electromyography (EMG) electrodes attached to their medial and lateral quadriceps muscles. Physical performance was assessed using the single-limb long hop for distance. Wavelet-derived mean instantaneous frequency (Mif) of flexor torque-time curves was significantly (p < 0.05) higher (i.e., less smooth) in ACLR-STGT subjects compared to the ACLD, ACLR-PT and control subjects. No significant differences existed for peak hamstrings strength (i.e., peak torque produced) or quadriceps antagonist EMG activity. Positive correlations were identified between hamstrings force steadiness and quadriceps antagonist activity for ACLD (r = 0.797), ACLR-PT (r = 0.467), and ACLR-STGT (r = 0.628) subjects. For ACLR-STGT subjects, reduced hamstrings force steadiness associated with poorer long-hop performance (r = -0.695). Reduced steadiness amongst ACLR-STGT subjects may reflect motor output variability of the antagonist (i.e., quadriceps dyskinesia) and/or agonist musculature-a maladaptive feature which potentially contributes to poorer single-limb hop performance. Measures of hamstring force steadiness in combination with traditional measures of peak hamstring strength provide valuable clinical information regarding knee joint function following ACL injury/ACLR.
Collapse
Affiliation(s)
- Adam L Bryant
- Faculty of Medicine, Dentistry and Health Sciences, The University of Melbourne, Melbourne, Victoria, Australia.
| | | | | |
Collapse
|
|
45
|
Krishnan C, Allen EJ, Williams GN. Effect of knee position on quadriceps muscle force steadiness and activation strategies. Muscle Nerve 2011; 43:563-73. [PMID: 21404288 PMCID: PMC3077092 DOI: 10.1002/mus.21981] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
INTRODUCTION In this study we investigated the effect of knee position on quadriceps force steadiness and activation strategies. METHODS Quadriceps force steadiness was evaluated in 22 volunteers at two knee positions by testing their ability to regulate submaximal force. Muscle activation strategies were studied in both time and frequency domains using surface electromyography. RESULTS Quadriceps force fluctuations and the associated agonist and antagonist activity were significantly higher at 90° than at 30° of flexion (P < 0.05). The quadriceps median frequency recorded at 30° was significantly higher than at 90° of flexion (P < 0.05). Regression analyses revealed that force steadiness was related to quadriceps activation and median frequency (P < 0.001), but not to hamstring coactivation (P > 0.05). CONCLUSIONS The results indicate that knee position significantly affects quadriceps force steadiness and activation strategies. This finding may have important implications for designing a force control testing protocol and interpreting test results.
Collapse
Affiliation(s)
- Chandramouli Krishnan
- Searle Laboratory, Sensory Motor Performance Program, Rehabilitation Institute of Chicago, Chicago, Illinois, USA.
| | | | | |
Collapse
|
|
46
|
Beck TW, Defreitas JM, Stock MS, Dillon MA. Effects of resistance training on force steadiness and common drive. Muscle Nerve 2011; 43:245-50. [PMID: 21254090 DOI: 10.1002/mus.21836] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The purpose of this study was to investigate the influence of an 8-week resistance training program on force steadiness and common drive for the vastus lateralis muscle. Eight untrained men performed a resistance training program. Before the program and at the end of each week, the subjects performed a trapezoid isometric muscle action of the leg extensors, and bipolar surface electromyographic signals were recorded from the vastus lateralis. The signals were decomposed into action potential trains that were cross-correlated to measure common drive. Force steadiness was quantified as the standard deviation of force during the constant-force portion of the trapezoid muscle action. The training program did not consistently affect force steadiness or common drive for any of the subjects. Although future studies are needed with different muscles and training programs, changes in the overall motor control scheme are not likely with resistance training.
Collapse
Affiliation(s)
- Travis W Beck
- Department of Health and Exercise Science, University of Oklahoma, Norman, OK 73019-6081, USA.
| | | | | | | |
Collapse
|
|
47
|
Oshita K, Yano S. Low-frequency Force Steadiness Practice in Plantar Flexor Muscle Reduces Postural Sway during Quiet Standing. J Physiol Anthropol 2011; 30:233-9. [DOI: 10.2114/jpa2.30.233] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022] Open
|
|
48
|
Mulder ER, Horstman AM, Gerrits K, Massa M, Kleine BU, de Haan A, Belavý DL, Felsenberg D, Zwarts M, Stegeman DF. Enhanced physiological tremor deteriorates plantar flexor torque steadiness after bed rest. J Electromyogr Kinesiol 2010; 21:384-93. [PMID: 21131213 DOI: 10.1016/j.jelekin.2010.10.009] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2010] [Revised: 10/18/2010] [Accepted: 10/18/2010] [Indexed: 11/17/2022] Open
Abstract
This study evaluated the effectiveness of resistance training to preserve submaximal plantar flexor (PF) torque steadiness following 60 days of bed rest (BR). Twenty-two healthy male subjects underwent either BR only (CTR, n=8), or BR plus resistance training (RT, n=14). The magnitude of torque fluctuations during steady submaximal isometric PF contractions (20%, 40%, 60% and 80% of maximum) were assessed before and after BR. Across contraction intensities, torque fluctuations (coefficient of variation, CV) increased more (P<0.05) after BR for CTR (from 0.31±0.10 to 0.92±0.63; P<0.001), than for RT (from 0.30±0.09 to 0.54±0.27; P<0.01). A shift in the spectral content of torque fluctuations towards increased rhythmic activity between 6.5 and 20Hz was observed in CTR only (P<0.05). H-reflex amplitude (H(max)/M(max) ratio) declined across groups from 0.57±0.18 before BR to 0.44±0.14 following BR (P<0.01) without correlation to CV. The present study showed that increased torque fluctuation after BR resulted from enhanced physiological tremor. Resistance training prevented the spectral shift in isometric PF torque fluctuation and offset ∼50% of the decline in performance associated with long-term BR.
Collapse
Affiliation(s)
- Edwin R Mulder
- Institute of Aerospace Medicine, Division of Space Physiology, German Space Center, Cologne, Germany.
| | | | | | | | | | | | | | | | | | | |
Collapse
|
|
49
|
Aagaard P, Suetta C, Caserotti P, Magnusson SP, Kjaer M. Role of the nervous system in sarcopenia and muscle atrophy with aging: strength training as a countermeasure. Scand J Med Sci Sports 2010; 20:49-64. [PMID: 20487503 DOI: 10.1111/j.1600-0838.2009.01084.x] [Citation(s) in RCA: 471] [Impact Index Per Article: 31.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Aging is characterized by loss of spinal motor neurons (MNs) due to apoptosis, reduced insulin-like growth factor I signaling, elevated amounts of circulating cytokines, and increased cell oxidative stress. The age-related loss of spinal MNs is paralleled by a reduction in muscle fiber number and size (sarcopenia), resulting in impaired mechanical muscle performance that in turn leads to a reduced functional capacity during everyday tasks. Concurrently, maximum muscle strength, power, and rate of force development are decreased with aging, even in highly trained master athletes. The impairment in muscle mechanical function is accompanied and partly caused by an age-related loss in neuromuscular function that comprise changes in maximal MN firing frequency, agonist muscle activation, antagonist muscle coactivation, force steadiness, and spinal inhibitory circuitry. Strength training appears to elicit effective countermeasures in elderly individuals even at a very old age (>80 years) by evoking muscle hypertrophy along with substantial changes in neuromuscular function, respectively. Notably, the training-induced changes in muscle mass and nervous system function leads to an improved functional capacity during activities of daily living.
Collapse
Affiliation(s)
- P Aagaard
- Institute of Sports Science and Clinical Biomechanics, University of Southern Denmark, Odense, Denmark.
| | | | | | | | | |
Collapse
|
|
50
|
Singh NB, Arampatzis A, Duda G, Heller MO, Taylor WR. Effect of fatigue on force fluctuations in knee extensors in young adults. PHILOSOPHICAL TRANSACTIONS. SERIES A, MATHEMATICAL, PHYSICAL, AND ENGINEERING SCIENCES 2010; 368:2783-2798. [PMID: 20439273 DOI: 10.1098/rsta.2010.0091] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
This study investigated the hypothesis that fatiguing exercises led to increased force fluctuations during submaximal isometric knee extensions and to decreased accuracy and steadiness in the time and frequency domains. Sixteen young adults (eight males, eight females) were tested, in a seated posture with 90 degrees knee flexion, to assess their ability to reproduce target extensor torques set at 15 per cent and 20 per cent of their maximum voluntary isometric contraction, both before and after fatiguing exercises. Normalized mean (NMAE) and peak (NPAE) of the absolute error were both used to quantify accuracy, whereas normalized standard deviation of the absolute error (NSAE) was used to quantify steadiness of the torque trials in the time domain. Mean and median power frequencies (MnPF, MdPF) and normalized peak power (NPkP) were used to assess the spectral structure of the torque signals. NMAE, NSAE and NPAE all showed excellent intra- as well as intersession reliabilities (intraclass correlation values greater than 0.75 and low standard error of measurement values), demonstrating repeatability of the test set-up. NMAE, NSAE and NPAE increased significantly post-fatigue (greater than 42%), together with a shift towards higher frequency (MnPF and MdPF) components, indicating that the set-up was sensitive enough to detect the decreased force accuracy and steadiness of the musculature after fatigue. Increased force variability in both the time and frequency domains could therefore explain decreased steadiness after fatigue.
Collapse
Affiliation(s)
- Navrag B Singh
- Julius Wolff Institute, Charité--Universitätsmedizin Berlin, Germany
| | | | | | | | | |
Collapse
|