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Akalu Y, Tallent J, Frazer AK, Siddique U, Rostami M, Vallance P, Howatson G, Walker S, Kidgell DJ. Strength-trained adults demonstrate greater corticoreticular activation versus untrained controls. Eur J Neurosci 2024; 59:2336-2352. [PMID: 38419404 DOI: 10.1111/ejn.16297] [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: 10/17/2023] [Revised: 02/08/2024] [Accepted: 02/12/2024] [Indexed: 03/02/2024]
Abstract
The rapid increase in strength following strength-training involves neural adaptations, however, their specific localisation remains elusive. Prior focus on corticospinal responses prompts this study to explore the understudied cortical/subcortical adaptations, particularly cortico-reticulospinal tract responses, comparing healthy strength-trained adults to untrained peers. Fifteen chronically strength-trained individuals (≥2 years of training, mean age: 24 ± 7 years) were compared with 11 age-matched untrained participants (mean age: 26 ± 8 years). Assessments included maximal voluntary force (MVF), corticospinal excitability using transcranial magnetic stimulation (TMS), spinal excitability (cervicomedullary stimulation), voluntary activation (VA) and reticulospinal tract (RST) excitability, utilizing StartReact responses and ipsilateral motor-evoked potentials (iMEPs) for the flexor carpi radialis muscle. Trained participants had higher normalized MVF (6.4 ± 1.1 N/kg) than the untrained participants (4.8 ± 1.3 N/kg) (p = .003). Intracortical facilitation was higher in the strength-trained group (156 ± 49%) (p = .02), along with greater VA (98 ± 3.2%) (p = .002). The strength-trained group displayed reduced short-interval-intracortical inhibition (88 ± 8.0%) compared with the untrained group (69 ± 17.5%) (p < .001). Strength-trained individuals exhibited a greater normalized rate of force development (38.8 ± 10.1 N·s-1/kg) (p < .009), greater reticulospinal gain (2.5 ± 1.4) (p = .02) and higher ipsilateral-to-contralateral MEP ratios compared with the untrained group (p = .03). Strength-trained individuals displayed greater excitability within the intrinsic connections of the primary motor cortex and the RST. These results suggest greater synaptic input from the descending cortico-reticulospinal tract to α-motoneurons in strength-trained individuals, thereby contributing to the observed increase in VA and MVF.
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Affiliation(s)
- Yonas Akalu
- Monash Exercise Neuroplasticity Research Unit, Department of Physiotherapy, School of Primary and Allied Health Care, Faculty of Medicine, Nursing and Health Science, Monash University, Frankston, Victoria, Australia
- Department of Human Physiology, School of Medicine, University of Gondar, Gondar, Ethiopia
| | - 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, Frankston, Victoria, Australia
- School of Sport, Rehabilitation and Exercise Sciences, University of Essex, Colchester, UK
| | - 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, Frankston, Victoria, Australia
| | - 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, Frankston, Victoria, Australia
| | - Mohamad Rostami
- Monash Exercise Neuroplasticity Research Unit, Department of Physiotherapy, School of Primary and Allied Health Care, Faculty of Medicine, Nursing and Health Science, Monash University, Frankston, Victoria, Australia
| | - Patrick Vallance
- Monash Exercise Neuroplasticity Research Unit, Department of Physiotherapy, School of Primary and Allied Health Care, Faculty of Medicine, Nursing and Health Science, Monash University, Frankston, Victoria, Australia
| | - Glyn Howatson
- Department of Sport, Exercise and Rehabilitation, Faculty of Health and Life Sciences, Northumbria University, Newcastle upon Tyne, UK
- Water Research Group, North-West University, Potchefstroom, South Africa
| | - Simon Walker
- NeuroMuscular Research Center, Faculty of Sport and Health Sciences, University of Jyväskylä, Jyväskylä, Finland
| | - 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, Frankston, Victoria, Australia
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Giuriato G, Romanelli MG, Bartolini D, Vernillo G, Pedrinolla A, Moro T, Franchi M, Locatelli E, Andani ME, Laginestra FG, Barbi C, Aloisi GF, Cavedon V, Milanese C, Orlandi E, De Simone T, Fochi S, Patuzzo C, Malerba G, Fabene P, Donadelli M, Stabile AM, Pistilli A, Rende M, Galli F, Schena F, Venturelli M. Sex differences in neuromuscular and biological determinants of isometric maximal force. Acta Physiol (Oxf) 2024; 240:e14118. [PMID: 38385696 DOI: 10.1111/apha.14118] [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: 11/21/2023] [Revised: 01/29/2024] [Accepted: 02/09/2024] [Indexed: 02/23/2024]
Abstract
AIM Force expression is characterized by an interplay of biological and molecular determinants that are expected to differentiate males and females in terms of maximal performance. These include muscle characteristics (muscle size, fiber type, contractility), neuromuscular regulation (central and peripheral factors of force expression), and individual genetic factors (miRNAs and gene/protein expression). This research aims to comprehensively assess these physiological variables and their role as determinants of maximal force difference between sexes. METHODS Experimental evaluations include neuromuscular components of isometric contraction, intrinsic muscle characteristics (proteins and fiber type), and some biomarkers associated with muscle function (circulating miRNAs and gut microbiome) in 12 young and healthy males and 12 females. RESULTS Male strength superiority appears to stem primarily from muscle size while muscle fiber-type distribution plays a crucial role in contractile properties. Moderate-to-strong pooled correlations between these muscle parameters were established with specific circulating miRNAs, as well as muscle and plasma proteins. CONCLUSION Muscle size is crucial in explaining the differences in maximal voluntary isometric force generation between males and females with similar fiber type distribution. Potential physiological mechanisms are seen from associations between maximal force, skeletal muscle contractile properties, and biological markers.
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Affiliation(s)
- Gaia Giuriato
- Department of Neurosciences, Biomedicine and Movement Sciences, University of Verona, Verona, Italy
- Surgical, Medical and Dental Department of Morphological Sciences Related to Transplant, Oncology and Regenerative Medicine, University of Modena and Reggio Emilia, Modena, Italy
| | - Maria Grazia Romanelli
- Department of Neurosciences, Biomedicine and Movement Sciences, University of Verona, Verona, Italy
| | - Desirée Bartolini
- Department of Pharmaceutical Sciences, University of Perugia, Perugia, Italy
| | - Gianluca Vernillo
- Department of Biomedical Sciences for Health, Università degli Studi di Milano, Milan, Italy
- Department of Social Sciences, University of Alberta - Augustana Campus, Camrose, Alberta, Canada
| | - Anna Pedrinolla
- Department of Neurosciences, Biomedicine and Movement Sciences, University of Verona, Verona, Italy
- Department of Cellular, Computational and Integrative Biology (CIBIO), University of Trento, Trento, Italy
| | - Tatiana Moro
- Department of Biomedical Sciences, University of Padova, Padova, Italy
| | - Martino Franchi
- Department of Biomedical Sciences, University of Padova, Padova, Italy
| | - Elena Locatelli
- Department of Neurosciences, Biomedicine and Movement Sciences, University of Verona, Verona, Italy
| | - Mehran Emadi Andani
- Department of Neurosciences, Biomedicine and Movement Sciences, University of Verona, Verona, Italy
| | - Fabio Giuseppe Laginestra
- Department of Neurosciences, Biomedicine and Movement Sciences, University of Verona, Verona, Italy
- Department of Anesthesiology, University of Utah, Utah, USA
| | - Chiara Barbi
- Department of Neurosciences, Biomedicine and Movement Sciences, University of Verona, Verona, Italy
| | - Gloria Fiorini Aloisi
- Department of Neurosciences, Biomedicine and Movement Sciences, University of Verona, Verona, Italy
| | - Valentina Cavedon
- Department of Neurosciences, Biomedicine and Movement Sciences, University of Verona, Verona, Italy
| | - Chiara Milanese
- Department of Neurosciences, Biomedicine and Movement Sciences, University of Verona, Verona, Italy
| | - Elisa Orlandi
- Department of Neurosciences, Biomedicine and Movement Sciences, University of Verona, Verona, Italy
| | - Tonia De Simone
- Department of Neurosciences, Biomedicine and Movement Sciences, University of Verona, Verona, Italy
| | - Stefania Fochi
- Department of Neurosciences, Biomedicine and Movement Sciences, University of Verona, Verona, Italy
| | - Cristina Patuzzo
- Department of Neurosciences, Biomedicine and Movement Sciences, University of Verona, Verona, Italy
| | - Giovanni Malerba
- Department of Neurosciences, Biomedicine and Movement Sciences, University of Verona, Verona, Italy
| | - Paolo Fabene
- Department of Neurosciences, Biomedicine and Movement Sciences, University of Verona, Verona, Italy
| | - Massimo Donadelli
- Department of Neurosciences, Biomedicine and Movement Sciences, University of Verona, Verona, Italy
| | - Anna Maria Stabile
- Department of Medicine and Surgery, Section of Human Anatomy, Clinical and Forensic, School of Medicine, University of Perugia, Perugia, Italy
| | - Alessandra Pistilli
- Department of Medicine and Surgery, Section of Human Anatomy, Clinical and Forensic, School of Medicine, University of Perugia, Perugia, Italy
| | - Mario Rende
- Department of Medicine and Surgery, Section of Human Anatomy, Clinical and Forensic, School of Medicine, University of Perugia, Perugia, Italy
| | - Francesco Galli
- Department of Pharmaceutical Sciences, University of Perugia, Perugia, Italy
| | - Federico Schena
- Department of Neurosciences, Biomedicine and Movement Sciences, University of Verona, Verona, Italy
| | - Massimo Venturelli
- Department of Neurosciences, Biomedicine and Movement Sciences, University of Verona, Verona, Italy
- Department of Internal Medicine, University of Utah, Utah, USA
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Pedrinolla A, Isanejad M, Antognelli C, Bartolini D, Borras C, Cavedon V, Di Sante G, Migni A, Mas-Bargues C, Milanese C, Baschirotto C, Modena R, Pistilli A, Rende M, Schena F, Stabile AM, Telesa NV, Tortorella S, Hemmings K, Vina J, Wang E, McArdle A, Jackson MJ, Venturelli M, Galli F. Randomised controlled trial combining vitamin E-functionalised chocolate with physical exercise to reduce the risk of protein-energy malnutrition in predementia aged people: study protocol for Choko-Age. BMJ Open 2023; 13:e072291. [PMID: 38135320 DOI: 10.1136/bmjopen-2023-072291] [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] [Indexed: 12/24/2023] Open
Abstract
OBJECTIVE Protein-energy malnutrition and the subsequent muscle wasting (sarcopenia) are common ageing complications. It is knowing to be also associated with dementia. Our programme will test the cytoprotective functions of vitamin E combined with the cortisol-lowering effect of chocolate polyphenols (PP), in combination with muscle anabolic effect of adequate dietary protein intake and physical exercise to prevent the age-dependent decline of muscle mass and its key underpinning mechanisms including mitochondrial function, and nutrient metabolism in muscle in the elderly. METHODS AND ANALYSIS In 2020, a 6-month double-blind randomised controlled trial in 75 predementia older people was launched to prevent muscle mass loss, in respond to the 'Joint Programming Initiative A healthy diet for a healthy life'. In the run-in phase, participants will be stabilised on a protein-rich diet (0.9-1.0 g protein/kg ideal body weight/day) and physical exercise programme (high-intensity interval training specifically developed for these subjects). Subsequently, they will be randomised into three groups (1:1:1). The study arms will have a similar isocaloric diet and follow a similar physical exercise programme. Control group (n=25) will maintain the baseline diet; intervention groups will consume either 30 g/day of dark chocolate containing 500 mg total PP (corresponding to 60 mg epicatechin) and 100 mg vitamin E (as RRR-alpha-tocopherol) (n=25); or the high polyphenol chocolate without additional vitamin E (n=25). Muscle mass will be the primary endpoint. Other outcomes are neurocognitive status and previously identified biomolecular indices of frailty in predementia patients. Muscle biopsies will be collected to assess myocyte contraction and mitochondrial metabolism. Blood and plasma samples will be analysed for laboratory endpoints including nutrition metabolism and omics. ETHICS AND DISSEMINATION All the ethical and regulatory approvals have been obtained by the ethical committees of the Azienda Ospedaliera Universitaria Integrata of Verona with respect to scientific content and compliance with applicable research and human subjects' regulation. Given the broader interest of the society toward undernutrition in the elderly, we identify four main target audiences for our research activity: national and local health systems, both internal and external to the project; targeted population (the elderly); general public; and academia. These activities include scientific workshops, public health awareness campaigns, project dedicated website and publication is scientific peer-review journals. TRIAL REGISTRATION NUMBER NCT05343611.
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Affiliation(s)
- Anna Pedrinolla
- Cellular, Computational and Integrative Biology, University of Trento, Trento, Italy
| | - Masoud Isanejad
- Centre for Integrated Research into Musculoskeletal Ageing (CIMA), Musculoskeletal & Ageing Science, University of Liverpool, Liverpool, UK
| | - Cinzia Antognelli
- Department of Medicine and Surgery, University of Perugia, Perugia, Italy
| | - Desirée Bartolini
- Department of Medicine and Surgery, Bioscience and Medical Embryology Division, University of Perugia, Perugia, Italy
| | - Consuelo Borras
- Department of Physiology, Faculty of Medicine, University of Valencia, Valencia, Spain
| | - Valentina Cavedon
- Department of Neuroscience, Biomedicine and Movement (DNBM), University of Verona, Verona, Italy
| | - Gabriele Di Sante
- Department of Neuroscience, Biomedicine and Movement (DNBM), University of Verona, Verona, Italy
| | - Anna Migni
- Department of Pharmaceutical Sciences, Lipidomics and Micronutrient, University of Perugia, Perugia, Italy
| | - Cristina Mas-Bargues
- Freshage Research Group, Department of Physiology, Faculty of Medicine, Centro de Investigación Biomédica en Red Fragilidad y Envejecimiento Saludable-Instituto de Salud Carlos III (CIBERFES-ISCIII), University of Valencia, Valencia, Spain
| | - Chiara Milanese
- Department of Neuroscience, Biomedicine and Movement (DNBM), University of Verona, Verona, Italy
| | - Claudia Baschirotto
- Department of Neuroscience, Biomedicine and Movement (DNBM), University of Verona, Verona, Italy
| | - Roberto Modena
- Department of Health and Social Sciences, Molde University College, Molde, Norway
| | - Alessandra Pistilli
- Department of Neuroscience, Biomedicine and Movement (DNBM), University of Verona, Verona, Italy
| | - Mario Rende
- Department of Neuroscience, Biomedicine and Movement (DNBM), University of Verona, Verona, Italy
| | - Federico Schena
- Department of Neuroscience, Biomedicine and Movement (DNBM), University of Verona, Verona, Italy
| | - Anna Maria Stabile
- Department of Neuroscience, Biomedicine and Movement (DNBM), University of Verona, Verona, Italy
| | | | | | - Kay Hemmings
- Centre for Integrated Research into Musculoskeletal Ageing (CIMA), Musculoskeletal & Ageing Science, University of Liverpool, Liverpool, UK
| | - Jose Vina
- Department of Physiology, Faculty of Medicine, University of Valencia, Valencia, Spain
| | - Eivind Wang
- Department of Health and Social Sciences, Molde University College, Molde, Norway
- St Olavs Hospital Trondheim University Hospital, Trondheim, Norway
| | - Anne McArdle
- Centre for Integrated Research into Musculoskeletal Ageing (CIMA), Musculoskeletal & Ageing Science, University of Liverpool, Liverpool, UK
| | - Malcolm J Jackson
- Centre for Integrated Research into Musculoskeletal Ageing (CIMA), Musculoskeletal & Ageing Science, University of Liverpool, Liverpool, UK
| | - Massimo Venturelli
- Department of Neuroscience, Biomedicine and Movement (DNBM), University of Verona, Verona, Italy
| | - Francesco Galli
- Department of Pharmaceutical Sciences, University of Perugia, Perugia, Italy
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Tøien T, Nielsen JL, Berg OK, Brobakken MF, Nyberg SK, Espedal L, Malmo T, Frandsen U, Aagaard P, Wang E. The impact of life-long strength versus endurance training on muscle fiber morphology and phenotype composition in older men. J Appl Physiol (1985) 2023; 135:1360-1371. [PMID: 37881849 PMCID: PMC10979801 DOI: 10.1152/japplphysiol.00208.2023] [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: 03/31/2023] [Revised: 10/11/2023] [Accepted: 10/25/2023] [Indexed: 10/27/2023] Open
Abstract
Aging is typically associated with decreased muscle strength and rate of force development (RFD), partly explained by motor unit remodeling due to denervation, and subsequent loss of fast-twitch type II myofibers. Exercise is commonly advocated to counteract this detrimental loss. However, it is unclear how life-long strength versus endurance training may differentially affect markers of denervation and reinnervation of skeletal myofibers and, in turn, affect the proportion and morphology of fast-twitch type II musculature. Thus, we compared fiber type distribution, fiber type grouping, and the prevalence of atrophic myofibers (≤1,494 µm2) in strength-trained (OS) versus endurance-trained (OE) master athletes and compared the results to recreationally active older adults (all >70 yr, OC) and young habitually active references (<30 yr, YC). Immunofluorescent stainings were performed on biopsy samples from vastus lateralis, along with leg press maximal strength and RFD measurements. OS demonstrated similar type II fiber distribution (OS: 52.0 ± 16.4%; YC: 51.1 ± 14.4%), fiber type grouping, maximal strength (OS: 170.0 ± 18.9 kg, YC: 151.0 ± 24.4 kg), and RFD (OS: 3,993 ± 894 N·s-1, YC: 3,470 ± 1,394 N·s-1) as young, and absence of atrophic myofibers (OS: 0.2 ± 0.7%; YC: 0.1 ± 0.4%). In contrast, OE and OC exhibited more atrophic fibers (OE: 1.2 ± 1.0%; OC: 1.1 ± 1.4%), more grouped fibers, and smaller proportion of type II fibers (OE: 39.3 ± 11.9%; OC: 35.0 ± 12.4%) than OS and YC (all P < 0.05). In conclusion, strength-trained master athletes were characterized by similar muscle morphology as young, which was not the case for recreationally active or endurance-trained old. These results indicate that strength training may preserve type II fibers with advancing age in older men, likely as a result of chronic use of high contractile force generation.NEW & NOTEWORTHY Aging is associated with loss of fast-twitch type II myofibers, motor unit remodeling, and grouping of myofibers. This study reveals, for the first time, that strength training preserves neural innervation of type II fibers, resulting in similar myofiber type distribution and grouping in life-long strength-trained master athletes as young moderately active adults. In contrast, life-long endurance-trained master athletes and recreationally active old adults demonstrated higher proportion of type I fibers accompanied by more marked grouping of type I myofibers, and more atrophic fibers compared with strength-trained master athletes and young individuals. Thus, strength training should be utilized as a training modality for preservation of fast-twitch musculature, maximal muscle strength, and rapid force capacity (RFD) with advancing age.
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Affiliation(s)
- Tiril Tøien
- Department of Health and Social Sciences, Molde University College, Molde, Norway
| | - Jakob Lindberg Nielsen
- Department of Sports Science and Clinical Biomechanics, Research Unit for Muscle Physiology and Biomechanics, University of Southern Denmark, Odense, Denmark
| | - Ole Kristian Berg
- Department of Health and Social Sciences, Molde University College, Molde, Norway
| | - Mathias Forsberg Brobakken
- Department of Health and Social Sciences, Molde University College, Molde, Norway
- Department of Psychosis and Rehabilitation, Psychiatry Clinic, St. Olavs University Hospital, Trondheim, Norway
| | - Stian Kwak Nyberg
- Department of Anesthesiology and Intensive Care, Drammen Hospital, Vestre Viken Hospital Trust, Drammen, Norway
| | - Lars Espedal
- Department of Health and Social Sciences, Molde University College, Molde, Norway
| | - Thomas Malmo
- Norwegian Defence University College, Norwegian Armed Forces, Oslo, Norway
| | - Ulrik Frandsen
- Department of Sports Science and Clinical Biomechanics, Research Unit for Muscle Physiology and Biomechanics, University of Southern Denmark, Odense, Denmark
| | - Per Aagaard
- Department of Sports Science and Clinical Biomechanics, Research Unit for Muscle Physiology and Biomechanics, University of Southern Denmark, Odense, Denmark
| | - Eivind Wang
- Department of Health and Social Sciences, Molde University College, Molde, Norway
- Department of Psychosis and Rehabilitation, Psychiatry Clinic, St. Olavs University Hospital, Trondheim, Norway
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Romare M, Elcadi GH, Johansson E, Tsaklis P. Relative Neuroadaptive Effect of Resistance Training along the Descending Neuroaxis in Older Adults. Brain Sci 2023; 13:brainsci13040679. [PMID: 37190644 DOI: 10.3390/brainsci13040679] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2023] [Revised: 04/01/2023] [Accepted: 04/16/2023] [Indexed: 05/17/2023] Open
Abstract
Age-related decline in voluntary force production represents one of the main contributors to the onset of physical disability in older adults and is argued to stem from adverse musculoskeletal alterations and changes along the descending neuroaxis. The neural contribution of the above is possibly indicated by disproportionate losses in voluntary activation (VA) compared to muscle mass. For young adults, resistance training (RT) induces muscular and neural adaptations over several levels of the central nervous system, contributing to increased physical performance. However, less is known about the relative neuroadaptive contribution of RT in older adults. The aim of this review was to outline the current state of the literature regarding where and to what extent neural adaptations occur along the descending neuroaxis in response to RT in older adults. We performed a literature search in PubMed, Google Scholar and Scopus. A total of 63 articles met the primary inclusion criteria and following quality analysis (PEDro) 23 articles were included. Overall, neuroadaptations in older adults seemingly favor top-down adaptations, where the preceding changes of neural drive from superior levels affect the neural output of lower levels, following RT. Moreover, older adults appear more predisposed to neural rather than morphological adaptations compared to young adults, a potentially important implication for the improved maintenance of neuromuscular function during aging.
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Affiliation(s)
- Mattias Romare
- ErgoMech-Lab, Department of Physical Education and Sport Science, University of Thessaly, 42100 Trikala, Greece
| | - Guilherme H Elcadi
- ErgoMech-Lab, Department of Physical Education and Sport Science, University of Thessaly, 42100 Trikala, Greece
- Division of Ergonomics, School of Engineering Sciences in Chemistry, Biotechnology and Health, KTH Royal Institute of Technology, 14157 Huddinge, Sweden
| | - Elin Johansson
- Pain in Motion Research Group, Departments of Human Physiology and Rehabilitation Sciences, Faculty of Physical Education and Physiotherapy, Vrije Universiteit Brussel, PC 1050 Brussel, Belgium
| | - Panagiotis Tsaklis
- ErgoMech-Lab, Department of Physical Education and Sport Science, University of Thessaly, 42100 Trikala, Greece
- Centre of Orthopaedics and Regenerative Medicine, C.O.R.E.-C.I.R.I., Aristotle University of Thessaloniki, 541 24 Thessaloniki, Greece
- Department of Molecular Medicine and Surgery, Karolinska Institute, SE-171 76 Solna, Sweden
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Effects of home-based bodyweight squat training on neuromuscular properties in community-dwelling older adults. Aging Clin Exp Res 2023; 35:1043-1053. [PMID: 36853505 DOI: 10.1007/s40520-023-02370-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2022] [Accepted: 02/15/2023] [Indexed: 03/01/2023]
Abstract
BACKGROUND It is important to investigate neural as well as muscle morphological adaptations to evaluate the effects of exercise training on older adults. AIMS This study was aimed to investigate the effects of home-based bodyweight squat training on neuromuscular adaptation in older adults. METHODS Twenty-five community-dwelling older adults (77.7 ± 5.0 years) were assigned to squat (SQU) or control (CON) groups. Those in the SQU group performed 100 bodyweight squats every day and the others in the CON group only performed daily activities for 4 months. Maximum knee extension torque and high-density surface electromyography during submaximal contraction were assessed. Individual motor units (MUs) were identified and divided into relatively low or high-recruitment threshold MU groups. Firing rates of each MU group were calculated. The muscle thickness and echo intensity of the lateral thigh were assessed using ultrasound. As physical tests, usual gait speed, timed up and go test, grip strength, and five-time chair stand test were performed. RESULTS While no improvements in muscle strength, muscle thickness, echo intensity, or physical tests were noted in either group, the firing rate of relatively low recruitment threshold MUs significantly decreased in the SQU group after intervention. CONCLUSIONS These results suggest that low-intensity home-based squat training could not improve markedly muscle strength or physical functions even if high-repetition and high frequency exercise, but could modulate slightly neural activation in community-dwelling older adults.
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Bilateral Improvements Following Unilateral Home-Based Training in Plantar Flexors: A Potential for Cross-Education in Rehabilitation. J Sport Rehabil 2023; 32:14-23. [PMID: 35894916 DOI: 10.1123/jsr.2021-0383] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2021] [Revised: 05/03/2022] [Accepted: 05/09/2022] [Indexed: 01/03/2023]
Abstract
CONTEXT Cross-education (CE) refers to neuromuscular gains in the untrained limb upon contralateral limb training. To date, only laboratory-based exercise programs have demonstrated CE. Home-based exercise prescription eliciting CE could have greater clinical applicability. OBJECTIVE To determine the effect of an 8-week, home-based unilateral strength training intervention on isokinetic muscle strength, muscular excitation, and power in trained and untrained plantar flexors. DESIGN Randomized controlled trial. METHODS Thirty-four healthy participants were randomized to intervention (n = 20) or control (n = 14). The intervention group completed 3 sets of 12 repetitions of progressively loaded unilateral calf raises 3 days per week. Concentric and eccentric peak torque were measured using isokinetic dynamometry at 30°/s and 120°/s. Maximal electromyogram amplitude was simultaneously measured. Power was measured using a jump mat. All variables were measured at preintervention, midintervention, and postintervention. RESULTS Strength significantly increased bilaterally pre-post at both velocities concentrically and eccentrically in intervention group participants. Maximal electromyogram amplitude significantly increased pre-post bilaterally at both velocities in the medial gastrocnemii of the intervention group. Power significantly increased bilaterally pre-post in the intervention group, with a dose-response effect demonstrated in the untrained plantar flexors. The CE effects of strength, power, and electromyogram activation were 23.4%, 14.6%, and 25.3%, respectively. All control group values were unchanged pre-post. CONCLUSION This study shows that a simple at-home unilateral plantar flexor exercise protocol induces significant increases in contralateral strength, muscular excitation, and power. These results suggest the applicability of CE in home rehabilitation programs aiming to restore or maintain neuromuscular function in inactive individuals or immobilized ankles.
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Tøien T, Unhjem R, Berg OK, Aagaard P, Wang E. Strength versus endurance trained master athletes: Contrasting neurophysiological adaptations. Exp Gerontol 2023; 171:112038. [PMID: 36442699 DOI: 10.1016/j.exger.2022.112038] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2022] [Revised: 11/11/2022] [Accepted: 11/21/2022] [Indexed: 11/27/2022]
Abstract
Neural factors play a critical role in the age-related decline in maximal strength and rate of force development (RFD). However, it is uncertain how the age-related attenuation in neuromuscular function may be mitigated in strength or endurance trained master athletes. In this study we applied evoked spinal motoneuron recordings to examine descending motor drive, i.e., efferent drive from supraspinal and spinal centres during maximal voluntary contraction (MVC; V-wave) and H-reflex excitability measured at 10 % MVC in older (>65 yrs) and younger (<35 yrs) strength athletes (n = 21), endurance athletes (n = 17) and untrained control participants (n = 30). Both strength (b = 0.09 [0.01-0.18], p = 0.038) and endurance training (b = 0.14 [0.04-0.23], p = 0.006) were associated with a high V-wave amplitude. This was likely explained by an elevated H-reflex excitability (b = 0.23 [0.11-0.35], p < 0.001) in endurance trained participants, which failed to be seen in strength trained participants. These contrasting neurophysiological properties were accompanied by different physiological traits; strength training was associated with high maximal strength (b = 107.5 [84.6 to 130.4] kg, p < 0.001) and RFD (b = 3171 [2248 to 4094] N‧s-1, p < 0.001), whereas endurance training was associated with elevated maximal oxygen uptake (V̇O2max; b = 13.6 [8.0-19.2] ml‧kg-1‧min-1, p < 0.001). This pattern was apparent irrespective of age, although all traits were negatively associated with advanced age (p < 0.05). In conclusion, strength trained individuals demonstrate higher descending motor drive (elevated V-wave responses), compared to age-matched untrained individuals. Endurance trained individuals also showed elevated V-wave responses, uniquely accompanied by enhanced α-motoneuron excitability and/or reduced pre/postsynaptic inhibition (elevated H-reflex responses). Since a high descending motor drive is a key component of strong muscle contractions, strength training should be emphasized to sustain the ability to carry out force-dependent tasks at older age.
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Affiliation(s)
- Tiril Tøien
- Department of Health and Social Sciences, Molde University College, Norway.
| | - Runar Unhjem
- Faculty of Education and Arts, Nord University, Bodø, Norway
| | - Ole Kristian Berg
- Department of Health and Social Sciences, Molde University College, Norway
| | - Per Aagaard
- Department of Sports Science and Clinical Biomechanics, Research Unit for Muscle Physiology and Biomechanics, University of Southern Denmark, Odense, Denmark
| | - Eivind Wang
- Department of Health and Social Sciences, Molde University College, Norway; Department of Østmarka, Division of Mental Health Care, St. Olavs Hospital, Trondheim University Hospital, Trondheim, Norway
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9
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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: 2] [Impact Index Per Article: 1.0] [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.
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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.
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10
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Tøien T, Malmo T, Espedal L, Wang E. Maximal intended velocity enhances strength training-induced neuromuscular stimulation in older adults. Eur J Appl Physiol 2022; 122:2627-2636. [PMID: 36112218 PMCID: PMC9613575 DOI: 10.1007/s00421-022-05045-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2022] [Accepted: 09/07/2022] [Indexed: 11/03/2022]
Abstract
AbstractThe age-related attenuation in neuromuscular function can be mitigated with strength training. Current recommendations for untrained and elderly recommend performing the strength training with a controlled movement velocity (CON). However, applying maximal intended velocity (MIV) in the concentric phase of movement may augment neuromuscular stimulation and potentially enhance training adaptations. Thus, applying rate of electromyography (EMG) rise (RER) recordings, we examined the acute early phase neuromuscular response to these two contraction types in quadriceps femoris during leg extension, along with actual movement velocity, in 12 older (76 ± 6 years) and 12 young men (23 ± 2 years). Results revealed that older adults had a lower one repetition maximum (1RM) than young (33 ± 9 kg vs. 50 ± 9 kg; p = 0.001) and lower actual velocity across relative intensities of ~ 10%, 30%, 50%, 70% and 90% of 1RM for CON and MIV (all p < 0.05). Older adults also had consistently reduced RER compared to young during both conditions (old: 1043–1810 μV; young: 1844–3015 μV; all p < 0.05). However, RER was higher in contractions with MIV compared to CON for both age groups, and across all intensities (98–674%, all p < 0.05). In conclusion, despite decreased maximal strength and attenuated neuromuscular response with advancing age, our results document an augmented neuromuscular activation when repetitions are performed with MIV in the concentric phase of movement.
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11
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The Application of Exercise Training for Diabetic Peripheral Neuropathy. J Clin Med 2021; 10:jcm10215042. [PMID: 34768562 PMCID: PMC8584831 DOI: 10.3390/jcm10215042] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2021] [Revised: 10/13/2021] [Accepted: 10/25/2021] [Indexed: 12/15/2022] Open
Abstract
Diabetic peripheral neuropathy (DPN) is the presence of symptoms and/or signs of peripheral nerve dysfunction in people with diabetes after the exclusion of other causes. It is associated with pain, paresthesia, sensory loss, muscle atrophy with fat infiltration, and muscular dysfunction typically starting distally in the feet and progressing proximally. Muscle deterioration within the leg and foot can lead to muscle dysfunction, reduced mobility, and increases the risk of disability, ulceration, and amputation. Exercise training is an established method for increasing the different components of physical fitness, including enhancing body composition and improving neuromuscular strength. A number of experimental studies have utilized exercise training to treat various impairments associated with DPN, such as nerve conduction velocity, pain tolerance, and balance. However, the broad spectrum of exercise training modalities implemented and differences in target outcome measurements have made it difficult to understand the efficacy of exercise training interventions or provide appropriate exercise prescription recommendations. Therefore, the aims of this review were to (1) briefly describe the pathophysiology of DPN and (2) discuss the effects of exercise training interventions on sensorimotor, metabolic, and physical functions in people with DPN.
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12
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Tøien T, Haglo H, Nyberg SK, Rao SV, Stunes AK, Mosti MP, Wang E. Maximal strength training-induced increase in efferent neural drive is not reflected in relative protein expression of SERCA. Eur J Appl Physiol 2021; 121:3421-3430. [PMID: 34498135 PMCID: PMC8571128 DOI: 10.1007/s00421-021-04807-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2021] [Accepted: 09/01/2021] [Indexed: 10/26/2022]
Abstract
INTRODUCTION Maximal strength training (MST), performed with heavy loads (~ 90% of one repetition maximum; 1RM) and few repetitions, yields large improvements in efferent neural drive, skeletal muscle force production, and skeletal muscle efficiency. However, it is elusive whether neural adaptations following such high intensity strength training may be accompanied by alterations in energy-demanding muscular factors. METHODS Sixteen healthy young males (24 ± 4 years) were randomized to MST 3 times per week for 8 weeks (n = 8), or a control group (CG; n = 8). Measurements included 1RM and rate of force development (RFD), and evoked potentials recordings (V-wave and H-reflex normalized to M-wave (M) in the soleus muscle) applied to assess efferent neural drive to maximally contracting skeletal muscle. Biopsies were obtained from vastus lateralis and analyzed by western blots and real-time PCR to investigate the relative protein expression and mRNA expression of Sarcoplasmic Reticulum Ca2+ ATPase (SERCA) 1 and SERCA2. RESULTS Significant improvements in 1RM (17 ± 9%; p < 0.001) and early (0-100 ms), late (0-200 ms) and maximal RFD (31-53%; p < 0.01) were observed after MST, accompanied by increased maximal Vmax/Msup-ratio (9 ± 14%; p = 0.046), with no change in H-reflex to M-wave ratio. No changes were observed in the CG. No pre- to post-training differences were found in mRNA or protein expressions of SERCA1 and SERCA2 in either group. CONCLUSION MST increased efferent neural drive to maximally contracting skeletal muscle, causing improved force production. No change was observed in SERCA expression, indicating that responses to high intensity strength training may predominantly be governed by neural adaptations.
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Affiliation(s)
- Tiril Tøien
- Department of Health and Social Sciences, Molde University College, Britvegen 2, 6410, Molde, Norway.
| | - Håvard Haglo
- Department of Health and Social Sciences, Molde University College, Britvegen 2, 6410, Molde, Norway.,Myworkout, Medical Rehabilitation Clinic, Trondheim, Norway
| | - Stian Kwak Nyberg
- Department of Circulation and Medical Imaging, Faculty of Medicine and Health Sciences, Norwegian University of Science and Technology, Trondheim, Norway
| | - Shalini Vasudev Rao
- Cambridge Institute, University of Cambridge, Cambridge, UK.,Department of Clinical and Molecular Medicine, Faculty of Medicine and Health Sciences, Norwegian University of Science and Technology, Trondheim, Norway
| | - Astrid Kamilla Stunes
- Department of Clinical and Molecular Medicine, Faculty of Medicine and Health Sciences, Norwegian University of Science and Technology, Trondheim, Norway.,Medical Clinic, St. Olavs University Hospital, Trondheim, Norway
| | - Mats Peder Mosti
- Department of Clinical and Molecular Medicine, Faculty of Medicine and Health Sciences, Norwegian University of Science and Technology, Trondheim, Norway.,Medical Clinic, St. Olavs University Hospital, Trondheim, Norway
| | - Eivind Wang
- Department of Health and Social Sciences, Molde University College, Britvegen 2, 6410, Molde, Norway.,Department of Medicine, University of Utah, Salt Lake City, UT, USA.,Department of Østmarka, Division of Mental Health Care, St. Olavs Hospital, Trondheim University Hospital, Trondheim, Norway
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13
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Walker S. Evidence of resistance training-induced neural adaptation in older adults. Exp Gerontol 2021; 151:111408. [PMID: 34022275 DOI: 10.1016/j.exger.2021.111408] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2021] [Revised: 05/04/2021] [Accepted: 05/17/2021] [Indexed: 11/25/2022]
Abstract
The deleterious effects of aging on force production are observable from the age of 40 upwards, depending on the measure. Neural mechanisms contributing to maximum force production and rate of force development have been suggested as descending drive from supraspinal centers, spinal motoneuron excitability, and corticospinal inhibition of descending drive; all of which influence motor unit recruitment and/or firing rate. Resistance-trained Master athletes offer a good source of information regarding the inevitable effects of aging despite the countermeasure of systematic resistance-training. However, most evidence of neural adaptation is derived from longitudinal intervention studies in previously untrained (i.e. resistance-training naïve) older adults. There is good evidence for the effect of resistance-training on the end-point of neural activation, i.e. motor unit behavior, but little to no data on the generation of descending drive from e.g. transcranial magnetic stimulation or cortical imaging studies in older adults. This, along with tracking master athletes over several years, would provide valuable information and could be the focus of future research.
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Affiliation(s)
- Simon Walker
- NeuroMuscular Research Center, Faculty of Sport and Health Sciences, University of Jyväskylä, Finland.
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14
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Berg OK, Stutzer JM, Hoff J, Wang E. Early Maximal Strength Training Improves Leg Strength and Postural Stability in Elderly Following Hip Fracture Surgery. Geriatr Orthop Surg Rehabil 2021; 12:21514593211015103. [PMID: 34017617 PMCID: PMC8114282 DOI: 10.1177/21514593211015103] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/12/2021] [Revised: 04/10/2021] [Accepted: 04/12/2021] [Indexed: 12/04/2022] Open
Abstract
Introduction: Hip fractures predominantly occur in the geriatric population and results in increased physical inactivity and reduced independency, largely influenced by a downward spiral of ambulatory capacity, related to loss of skeletal muscle strength and postural stability. Thus, effective postoperative treatment, targeting improvements in muscle strength, is sought after. Materials & Methods: Twenty-one hip fracture patients (>65 yr) were randomized to 8 weeks of either conventional physiotherapy control group (CG), or leg press and hip abduction maximal strength training (MST) 3 times per week. MST was performed applying heavy loads (85-90% of 1 repetition maximum; 1RM) and 4-5 repetitions in 4 sets. Maximal strength (bi- and unilateral 1RM), postural stability (unipedal stance test; UPS), and DEXA-scan bone mineral content/ density (BMC/BMD) were measured before and after the 8-week rehabilitation. Results: Both MST and conventional physiotherapy improved bilateral leg press 1RM by 41 ± 27 kg and 29 ± 17 kg, respectively (both p < 0.01), while unilateral leg press 1RM only increased after MST (within group and between groups difference: both p < 0.05). MST also resulted in an increase in abduction 1RM in both the fractured (5 kg, 95%CI: 2-7; p < 0.01) and healthy limb (6 kg, 95%CI: 3-9; p < 0.01), while no such improvement was apparent in the CG (between groups difference: p < 0.01). Finally, MST improved UPS of the fractured limb (p < 0.05). No differences were observed in BMC or BMD following the 8 weeks. Discussion: Early postoperative MST improved lower extremities maximal muscle strength more than conventional physiotherapy and was accompanied by improvements in postural stability. Conclusion: Implementing MST in early rehabilitation after hip fracture surgery should be considered as a relevant treatment to curtail the downward spiral of reduced ambulatory capacity typical for this patient group, possibly reducing the risk of recuring falls and excess mortality. Trial Registration: https://clinicaltrials.gov/ct2/show/NCT03030092
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Affiliation(s)
- Ole Kristian Berg
- Faculty of Health and Social Sciences, Molde University College, Molde, Norway.,Department of Orthopedic Surgery, Møre and Romsdal Hospital Trust, Molde Hospital, Molde, Norway
| | - Jens-Meinhard Stutzer
- Department of Orthopedic Surgery, Møre and Romsdal Hospital Trust, Molde Hospital, Molde, Norway
| | - Jan Hoff
- Department of Circulation and Medical Imaging, Faculty of Medicine and Health Sciences, Norwegian University of Science and Technology, Trondheim, Norway.,Department of Physical Medicine and Rehabilitation, St. Olavs Hospital, Trondheim University Hospital, Norway.,The Exercise Clinic at Myworkout, Trondheim, Norway
| | - Eivind Wang
- Faculty of Health and Social Sciences, Molde University College, Molde, Norway.,Department of Circulation and Medical Imaging, Faculty of Medicine and Health Sciences, Norwegian University of Science and Technology, Trondheim, Norway
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15
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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: 1] [Impact Index Per Article: 0.3] [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.
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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
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16
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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: 0] [Impact Index Per Article: 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.
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17
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Hortobágyi T, Granacher U, Fernandez-Del-Olmo M, Howatson G, Manca A, Deriu F, Taube W, Gruber M, Márquez G, Lundbye-Jensen J, Colomer-Poveda D. Functional relevance of resistance training-induced neuroplasticity in health and disease. Neurosci Biobehav Rev 2020; 122:79-91. [PMID: 33383071 DOI: 10.1016/j.neubiorev.2020.12.019] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2020] [Revised: 12/18/2020] [Accepted: 12/19/2020] [Indexed: 01/13/2023]
Abstract
Repetitive, monotonic, and effortful voluntary muscle contractions performed for just a few weeks, i.e., resistance training, can substantially increase maximal voluntary force in the practiced task and can also increase gross motor performance. The increase in motor performance is often accompanied by neuroplastic adaptations in the central nervous system. While historical data assigned functional relevance to such adaptations induced by resistance training, this claim has not yet been systematically and critically examined in the context of motor performance across the lifespan in health and disease. A review of muscle activation, brain and peripheral nerve stimulation, and imaging data revealed that increases in motor performance and neuroplasticity tend to be uncoupled, making a mechanistic link between neuroplasticity and motor performance inconclusive. We recommend new approaches, including causal mediation analytical and hypothesis-driven models to substantiate the functional relevance of resistance training-induced neuroplasticity in the improvements of gross motor function across the lifespan in health and disease.
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Affiliation(s)
- Tibor Hortobágyi
- Center for Human Movement Sciences, University of Groningen, University Medical CenterGroningen, Groningen, Netherlands.
| | - Urs Granacher
- Division of Training and Movement Sciences, Research Focus Cognition Sciences, University of Potsdam, Potsdam, Germany
| | - Miguel Fernandez-Del-Olmo
- Area of Sport Sciences, Faculty of Sports Sciences and Physical Education, Center for Sport Studies, King Juan Carlos University, Madrid, Spain
| | - Glyn Howatson
- Department of Sport, Exercise and Rehabilitation, Northumbria University, Newcastle, UK; Water Research Group, North West University, Potchefstroom, South Africa
| | - Andrea Manca
- Department of Biomedical Sciences, University of Sassari, Sassari, Italy
| | - Franca Deriu
- Department of Biomedical Sciences, University of Sassari, Sassari, Italy
| | - Wolfgang Taube
- Department of Neurosciences and Movement Sciences, University of Fribourg, Fribourg, Switzerland
| | - Markus Gruber
- Human Performance Research Centre, Department of Sport Science, University of Konstanz, Konstanz, Germany
| | - Gonzalo Márquez
- Department of Physical Education and Sport, Faculty of Sports Sciences and Physical Education, University of A Coruña, A Coruña, Spain
| | - Jesper Lundbye-Jensen
- Movement & Neuroscience, Department of Nutrition, Exercise & Sports Department of Neuroscience, University of Copenhagenk, Faculty of Health Science, Universidad Isabel I, Burgos, Spain
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18
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Cluster training sets is an important stimulus for promoting gains in muscle power regardless of resistance training program design in older women. Sci Sports 2020. [DOI: 10.1016/j.scispo.2019.08.003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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19
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Helgerud J, Thomsen SN, Hoff J, Strandbråten A, Leivseth G, Unhjem R, Wang E. Maximal strength training in patients with Parkinson's disease: impact on efferent neural drive, force-generating capacity, and functional performance. J Appl Physiol (1985) 2020; 129:683-690. [PMID: 32790593 DOI: 10.1152/japplphysiol.00208.2020] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Parkinson's disease (PD) is characterized by progressive neurological deterioration, typically accompanied by reductions in skeletal muscle force-generating capacity (FGC) and functional performance. Physical activity has the potential to counteract this debilitating outcome, however, it is elusive if high-intensity strength training included in conventional treatment may improve results. Therefore, we randomly assigned 22 PD patients (74 ± 9 yr) to conventional rehabilitation with or without maximal strength training (MST) performed as leg press and chest press at ~90% of one repetition maximum (1RM), five times per week for 4 wk. FGC, physical performance, and efferent neural drive assessed as evoked potentials (V-wave normalized to M-wave in m. soleus) were measured following training. Results revealed that only MST improved 1RM leg press (101 ± 23 to 118 ± 18 kg) and chest press (36 ± 15 to 41 ± 15 kg), plantar flexion maximal voluntary contraction (235 ± 125 to 293 ± 158 N·m), and rate of force development (373 ± 345 to 495 ± 446 N·m·s-1; all P < 0.05; different from controls P < 0.05). FGC improvements were accompanied by an increased efferent neural drive to maximally contracting musculature (V-to-M ratio: 0.17 ± 0.12 to 0.24 ± 0.15; P < 0.05; different from controls P < 0.05), improved physical performance (stair climbing: 21.0 ± 9.2 to 14.4 ± 5.2 s; timed up and go: 7.8 ± 3.3 to 6.2 ± 2.5 s; both P < 0.05), and self-perceived improvement in health (3.1 ± 0.5 to 2.6 ± 0.9) and social activities functioning (2.2 ± 1.0 to 1.5 ± 1.1; both P < 0.05). No changes were observed in the control group. In conclusion, this study shows that MST improves FGC, neuromuscular function, and functional performance and advocates that high-intensity strength training should be implemented as an adjunct therapy in the treatment of PD patients.NEW & NOTEWORTHY This randomized, controlled trial documents that supervised high-intensity strength training improves efferent neural drive, maximal muscle strength, rate of force development, and functional performance in patients with Parkinson's disease (PD). In contrast, no differences were observed in these outcome variables in patients receiving conventional treatment consisting of recreational physical activity with low-to-medium intensity. Consequently, this study advocates that high-intensity strength training should be implemented in the clinical treatment of PD patients.
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Affiliation(s)
- J Helgerud
- Department of Circulation and Medical Imaging, Faculty of Medicine and Health Sciences, Norwegian University of Science and Technology, Trondheim, Norway.,Myworkout, Medical Rehabilitation Clinic, Trondheim, Norway
| | - S N Thomsen
- Centre for Physical Activity Research, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark
| | - J Hoff
- Myworkout, Medical Rehabilitation Clinic, Trondheim, Norway.,Department of Physical Medicine and Rehabilitation, St. Olavs University Hospital, Trondheim, Norway
| | - A Strandbråten
- Hokksund Medical Rehabilitation Center, Hokksund, Norway
| | - G Leivseth
- Department of Clinical Medicine, Arctic University of Norway, Tromsø, Norway
| | - R Unhjem
- Faculty of Nursing and Health Sciences, Nord University, Bodø, Norway
| | - E Wang
- Department of Circulation and Medical Imaging, Faculty of Medicine and Health Sciences, Norwegian University of Science and Technology, Trondheim, Norway.,Faculty of Health Sciences and Social Care, Molde University College, Molde, Norway.,Department of Internal Medicine, University of Utah, Salt Lake City, Utah.,Department of Rehabilitation, Rīga Stradiņš University, Riga, Latvia
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20
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Unhjem R, Tøien T, Kvellestad ACG, Øren TS, Wang E. External Resistance Is Imperative for Training-Induced Efferent Neural Drive Enhancement in Older Adults. J Gerontol A Biol Sci Med Sci 2020; 76:224-232. [DOI: 10.1093/gerona/glaa160] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2020] [Indexed: 11/13/2022] Open
Abstract
Abstract
Strength training performed with heavy loads and maximal intended velocity is documented to enhance efferent neural drive to maximally contracting musculature in older adults. However, it remains unclear whether the neural plasticity following training result from motor skill learning or if external resistance is a prerequisite. To investigate this, we assessed electrically evoked potentials (H-reflex and V-waves normalized to maximal M-wave) and voluntary activation (VA) in 36 older adults (73 ± 4 years) randomized to 3 weeks of plantar flexion strength training, with (maximal strength training [MST]) or without (unloaded ballistic training [UBT]) heavy external loading (90% of one repetition maximum), or a control group. Both training groups aimed to execute the concentric phase of movement as fast and forcefully as possible. The MST group improved maximal voluntary contraction (MVC) and rate of force development (RFD) by 18% ± 13% (p = .001; Hedges g = 0.66) and 35% ± 17% (p < .001; g = 0.94), respectively, and this was different (MVC: p = .013; RFD: p = .001) from the UBT group which exhibited a 7% ± 8% (p = .033; g = 0.32) increase in MVC and a tendency to increase RFD (p = .119; g = 0.22). Concomitant improvements in efferent neural drive (Vmax/Msup ratio: 0.14 ± 0.08 to 0.24 ± 0.20; p = .010) and a tendency towards increased VA (79% ± 9% to 84% ± 5%; p = .098), were only apparent after MST. No changes were observed in Hmax/Mmax ratio for the groups. In conclusion, external loading during exercise training appears to be a prerequisite for efferent neural drive enhancement in older adults. Thus, strength training with heavy loads should be recommended to counteract the typically observed age-related decline in motoneuron firing frequency and recruitment.
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Affiliation(s)
- Runar Unhjem
- Faculty of Nursing and Health Sciences, Nord University, Bodø, Norway
| | - Tiril Tøien
- Department of Health and Social Sciences, Molde University College, Norway
| | - Ann Charlotte Gjertsen Kvellestad
- Department of Circulation and Medical Imaging, Faculty of Medicine and Health Sciences, Norwegian University of Science and Technology, Trondheim, Norway
| | - Thomas Storehaug Øren
- Department of Circulation and Medical Imaging, Faculty of Medicine and Health Sciences, Norwegian University of Science and Technology, Trondheim, Norway
| | - Eivind Wang
- Department of Health and Social Sciences, Molde University College, Norway
- Department of Circulation and Medical Imaging, Faculty of Medicine and Health Sciences, Norwegian University of Science and Technology, Trondheim, Norway
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21
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Cogliati M, Cudicio A, Toscani F, Gaffurini P, Bissolotti LM, Orizio C, Negro F. Normalized maximal rate of torque development during voluntary and stimulated static contraction in human tibialis anterior: Influence of age. Exp Gerontol 2020; 138:110999. [PMID: 32512142 DOI: 10.1016/j.exger.2020.110999] [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: 02/27/2020] [Revised: 05/12/2020] [Accepted: 06/03/2020] [Indexed: 12/25/2022]
Abstract
The risk of falling in older adults has been related, among other factors, to the reduction of the rate of torque development (RTD) with age. It is well known that both structural/peripheral and neural factors can influence the RTD. The purpose of this study was to compare the normalized RTD in young and older participants obtained during a) rapid voluntary tension production and b) neuromuscular electrical stimulation. The tibialis anterior of 19 young subjects (10 males and 9 females; age 21-33 years old) and 19 older participants (10 males and 9 females; age 65-80 years old) was studied. The subjects performed a series of maximal isometric explosive dorsiflexions and underwent trains of supra-maximal electrical stimulations (35 Hz) on the tibialis anterior motor point. Muscle shortening was indirectly measured using a laser (surface mechanomyogram, MMG). Both torque and MMG were normalized to their maximum value. Using a 20 ms sliding window on the normalized torque signal, the normalized maximum RTD was calculated for both voluntary and stimulated contractions. Active stiffness of the muscle- tendon unit was calculated as the area of the normalized torque with respect to the normalized MMG. Normalized maximum RTD was found significantly lower in older adults during voluntary activity (young: 751.9 ± 216.3%/s and old: 513.9 ± 173.9%/s; P < .001), and higher during stimulated contractions (young: 753.1 ± 225.9%/s and old: 890.1 ± 221.3%/s; P = .009). Interestingly, active stiffness was also higher in older adults (young: 3524.6 ± 984.6‰ and old 4144.6 ± 816.6‰; P = .041) and significantly correlated to the normalized maximum RTD during stimulated contractions. This dichotomy suggests that modifications in the structural/peripheral muscle properties are not sufficient to counteract the age-related decrease in neural drive to the muscle during voluntary isometric contractions in aged participants.
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Affiliation(s)
- M Cogliati
- Centre of Research on the Neuromuscular Function and the Adapted Motor Activity, "Teresa Camplani" University of Brescia, Viale Europa, 11, 25123 Brescia, Italy
| | - A Cudicio
- Centre of Research on the Neuromuscular Function and the Adapted Motor Activity, "Teresa Camplani" University of Brescia, Viale Europa, 11, 25123 Brescia, Italy
| | - F Toscani
- Department of Clinical and Experimental Sciences, University of Brescia, Viale Europa, 11, 25123 Brescia, Italy
| | - P Gaffurini
- Rehabilitation Service, Fondazione Teresa Camplani-Casa di Cura Domus Salutis, Via Lazzaretto, 3, 25123 Brescia, Italy
| | - L M Bissolotti
- Rehabilitation Service, Fondazione Teresa Camplani-Casa di Cura Domus Salutis, Via Lazzaretto, 3, 25123 Brescia, Italy
| | - C Orizio
- Department of Clinical and Experimental Sciences, University of Brescia, Viale Europa, 11, 25123 Brescia, Italy; Centre of Research on the Neuromuscular Function and the Adapted Motor Activity, "Teresa Camplani" University of Brescia, Viale Europa, 11, 25123 Brescia, Italy.
| | - F Negro
- Department of Clinical and Experimental Sciences, University of Brescia, Viale Europa, 11, 25123 Brescia, Italy; Centre of Research on the Neuromuscular Function and the Adapted Motor Activity, "Teresa Camplani" University of Brescia, Viale Europa, 11, 25123 Brescia, Italy
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22
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Carneiro MAS, de Oliveira Júnior GN, de Sousa JFR, Santagnello SB, Souza MVC, Orsatti FL. Effects of cluster training sets on muscle power and force–velocity relationship in postmenopausal women. SPORT SCIENCES FOR HEALTH 2020. [DOI: 10.1007/s11332-019-00599-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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23
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Øvretveit K. High-Intensity, Non-Sport-Specific Strength and Conditioning for Brazilian Jiu-Jitsu Athletes: Theoretical and Practical Considerations. Strength Cond J 2020. [DOI: 10.1519/ssc.0000000000000542] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
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24
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Cross-education: effects of age on rapid and maximal voluntary contractile characteristics in males. Eur J Appl Physiol 2019; 119:1313-1322. [DOI: 10.1007/s00421-019-04123-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2018] [Accepted: 03/08/2019] [Indexed: 10/27/2022]
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25
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Øvretveit K, Tøien T. Maximal Strength Training Improves Strength Performance in Grapplers. J Strength Cond Res 2019; 32:3326-3332. [PMID: 30247275 DOI: 10.1519/jsc.0000000000002863] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Øvretveit, K and Tøien, T. Maximal strength training improves strength performance in grapplers. J Strength Cond Res 32(12): 3326-3332, 2018-The aim of this study was to assess the short-term effects of maximal strength training (MST) as an accessory to grappling training on strength performance in competitive Brazilian Jiu-Jitsu (BJJ) athletes. Fourteen male BJJ athletes underwent measurements of 1 repetition maximum (1RM) in the squat and bench press, rate of force development (RFD) and peak force (PF) in the squat jump, countermovement jump (CMJ) height, and muscular endurance in pull-ups, sit-ups, and push-ups. After baseline measurements, subjects were randomly allocated to either an MST group or control group (CON). The MST intervention consisted of 4 × 4 repetitions at ≥ 85% of 1RM in the squat and bench press, and 4 sets of pull-ups to failure, performed 3× per week. Both groups were instructed to maintain their BJJ training and avoid additional strength training. Maximal strength training improved 1RM in the squat and bench press by 15 ± 9% (p = 0.02) and 11 ± 3% (p = 0.03), respectively, and CMJ height by 9 ± 7% (p = 0.04). Muscular endurance performance increased by 33 ± 33% in pull-ups (p = 0.03), 32 ± 12% in push-ups (p = 0.03), and 13 ± 13% in sit-ups (p = 0.03). Increases in RFD (35 ± 55%, p = 0.13) and PF (8 ± 9%, p = 0.09) did not reach significance. No improvements were apparent from BJJ training alone (p > 0.05). These findings suggest that MST is a potent approach to rapid improvements in maximal strength, power, and muscular endurance in active grapplers.
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Affiliation(s)
- Karsten Øvretveit
- Department of Sociology and Political Science, Faculty of Social and Educational Sciences, Norwegian University of Science and Technology, Trondheim, Norway
| | - Tiril Tøien
- Department of Circulation and Medical Imaging, Faculty of Medicine and Health Sciences, Norwegian University of Science and Technology, Trondheim, Norway
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26
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Green LA, Gabriel DA. The effect of unilateral training on contralateral limb strength in young, older, and patient populations: a meta-analysis of cross education. PHYSICAL THERAPY REVIEWS 2018. [DOI: 10.1080/10833196.2018.1499272] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Affiliation(s)
- Lara A. Green
- Department of Kinesiology, Brock University, St. Catharines, ON, Canada
| | - David A. Gabriel
- Department of Kinesiology, Brock University, St. Catharines, ON, Canada
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27
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Tøien T, Pedersen Haglo H, Unhjem R, Hoff J, Wang E. Maximal strength training: the impact of eccentric overload. J Neurophysiol 2018; 120:2868-2876. [PMID: 30332319 DOI: 10.1152/jn.00609.2018] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
The search for the most potent strength training intervention is continuous. Maximal strength training (MST) yields large improvements in force-generating capacity (FGC), largely attributed to efferent neural drive enhancement. However, it remains elusive whether eccentric overload, before the concentric phase, may augment training-induced neuromuscular adaptations. A total of 53 23 ± 3 (SD)-yr-old untrained males were randomized to either a nontraining control group (CG) or one of two training groups performing leg press strength training with linear progression, three times per week for 8 wk. The first training group carried out MST with four sets of four repetitions at ~90% one-repetition maximum (1RM) in both action phases. The second group performed MST with an augmented eccentric load of 150% 1RM (eMST). Measurements were taken of 1RM and rate of force development (RFD), countermovement jump (CMJ) performance, and evoked potentials recordings [V-wave (V) and H-reflex (H) normalized to M-wave (M) in musculus soleus]. 1RM increased from 133 ± 16 to 157 ± 23 kg and 123 ± 18 to 149 ± 22 kg and CMJ by 2.3 ± 3.6 and 2.2 ± 3.7cm for MST and eMST, respectively (all P < 0.05). Early, late, and maximal RFD increased in both groups [634-1,501 N/s (MST); 644-2,111 N/s (eMST); P < 0.05]. These functional improvements were accompanied by increased V/M-ratio (MST: 0.34 ± 0.11 to 0.42 ± 14; eMST: .36 ± 0.14 to 0.43 ± 13; P < 0.05). Resting H/M-ratio remained unchanged. Training-induced improvements did not differ. All increases, except for CMJ, were different from the CG. MST is an enterprise for large gains in FGC and functional performance. Eccentric overload did not induce additional improvements, suggesting firing frequency and motor unit recruitment during MST may be maximal. NEW & NOTEWORTHY This is the first study to apply evoked potential recordings to investigate effects on efferent neural drive following high-intensity strength training with and without eccentric overload in a functionally relevant lower extremity exercise. We document that eccentric overload does not augment improvements in efferent neural drive or muscle force-generating capacity, suggesting that high-intensity concentric loads may maximally tax firing frequency and motor unit recruitment.
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Affiliation(s)
- Tiril Tøien
- Department of Circulation and Medical Imaging, Faculty of Medicine, Norwegian University of Science and Technology , Trondheim , Norway
| | - Håvard Pedersen Haglo
- Department of Circulation and Medical Imaging, Faculty of Medicine, Norwegian University of Science and Technology , Trondheim , Norway
| | - Runar Unhjem
- Faculty of Professional Studies, Nord University , Bodø , Norway
| | - Jan Hoff
- Department of Circulation and Medical Imaging, Faculty of Medicine, Norwegian University of Science and Technology , Trondheim , Norway.,Department of Physical Medicine and Rehabilitation, St. Olav's University Hospital , Trondheim , Norway
| | - Eivind Wang
- Department of Circulation and Medical Imaging, Faculty of Medicine, Norwegian University of Science and Technology , Trondheim , Norway.,Department of Health and Social Sciences, Molde University College , Norway.,Department of Medicine, University of Utah , Salt Lake City, Utah
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28
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Berg OK, Kwon OS, Hureau TJ, Clifton HL, Thurston T, Le Fur Y, Jeong EK, Amann M, Richardson RS, Trinity JD, Wang E, Layec G. Maximal strength training increases muscle force generating capacity and the anaerobic ATP synthesis flux without altering the cost of contraction in elderly. Exp Gerontol 2018; 111:154-161. [PMID: 30031838 DOI: 10.1016/j.exger.2018.07.013] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2018] [Revised: 07/09/2018] [Accepted: 07/18/2018] [Indexed: 01/09/2023]
Abstract
Aging is associated with a progressive decline in skeletal muscle function, then leading to impaired exercise tolerance. Maximal strength training (MST) appears to be a practical and effective intervention to increase both exercise capacity and efficiency. However, the underlying physiological mechanisms responsible for these functional improvements are still unclear. Accordingly, the purpose of this study was to examine the intramuscular and metabolic adaptations induced by 8 weeks of knee-extension MST in the quadriceps of 10 older individuals (75 ± 9 yrs) by employing a combination of molecular, magnetic resonance 1H-imaging and 31P-spectroscopy, muscle biopsies, motor nerve stimulation, and indirect calorimetry techniques. Dynamic and isometric muscle strength were both significantly increased by MST. The greater torque-time integral during sustained isometric maximal contraction post-MST (P = 0.002) was associated with increased rates of ATP synthesis from anaerobic glycolysis (PRE: 10 ± 7 mM·min-1; POST: 14 ± 7 mM·min-1, P = 0.02) and creatine kinase reaction (PRE: 31 ± 10 mM·min-1; POST: 41 ± 10 mM·min-1, P = 0.006) such that the ATP cost of contraction was not significantly altered. Expression of fast myosin heavy chain, quadriceps muscle volume, and submaximal cycling net efficiency were also increased with MST (P = 0.005; P = 0.03 and P = 0.03, respectively). Overall, MST induced a shift toward a more glycolytic muscle phenotype allowing for greater muscle force production during sustained maximal contraction. Consequently, some of the MST-induced improvements in exercise tolerance might stem from a greater anaerobic capacity to generate ATP, while the improvement in exercise efficiency appears to be independent from an alteration in the ATP cost of contraction.
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Affiliation(s)
- Ole Kristian Berg
- Faculty of Health and Social Sciences, Molde University College, Molde, Norway.
| | - Oh Sung Kwon
- Department of Internal Medicine, Division of Geriatrics, University of Utah, Salt Lake City, UT, USA; Geriatric Research, Education, and Clinical Center, George E. Whalen VA Medical Center, Salt Lake City, UT, USA
| | - Thomas J Hureau
- Department of Internal Medicine, Division of Geriatrics, University of Utah, Salt Lake City, UT, USA; Geriatric Research, Education, and Clinical Center, George E. Whalen VA Medical Center, Salt Lake City, UT, USA
| | - Heather L Clifton
- Department of Internal Medicine, Division of Geriatrics, University of Utah, Salt Lake City, UT, USA; Geriatric Research, Education, and Clinical Center, George E. Whalen VA Medical Center, Salt Lake City, UT, USA
| | - Taylor Thurston
- Department of Internal Medicine, Division of Geriatrics, University of Utah, Salt Lake City, UT, USA; Geriatric Research, Education, and Clinical Center, George E. Whalen VA Medical Center, Salt Lake City, UT, USA; Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, UT, USA
| | - Yann Le Fur
- CRMBM, Aix-Marseille Universite, CNRS 7339, Marseille, France
| | - Eun-Kee Jeong
- Department of Radiology, Utah Center for Advanced Imaging Research, University of Utah, Salt Lake City, UT, USA
| | - Markus Amann
- Geriatric Research, Education, and Clinical Center, George E. Whalen VA Medical Center, Salt Lake City, UT, USA; Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, UT, USA; Department of Anesthesiology, University of Utah, Salt Lake City, UT, USA
| | - Russel S Richardson
- Department of Internal Medicine, Division of Geriatrics, University of Utah, Salt Lake City, UT, USA; Geriatric Research, Education, and Clinical Center, George E. Whalen VA Medical Center, Salt Lake City, UT, USA; Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, UT, USA
| | - Joel D Trinity
- Department of Internal Medicine, Division of Geriatrics, University of Utah, Salt Lake City, UT, USA; Geriatric Research, Education, and Clinical Center, George E. Whalen VA Medical Center, Salt Lake City, UT, USA; Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, UT, USA
| | - Eivind Wang
- Faculty of Health and Social Sciences, Molde University College, Molde, Norway; Department of Internal Medicine, Division of Geriatrics, University of Utah, Salt Lake City, UT, USA; Department of Medicine, Norwegian University of Science and Technology, Trondheim, Norway; Department of Research and Development, St. Olav's University Hospital, Trondheim, Norway
| | - Gwenael Layec
- Department of Internal Medicine, Division of Geriatrics, University of Utah, Salt Lake City, UT, USA; Geriatric Research, Education, and Clinical Center, George E. Whalen VA Medical Center, Salt Lake City, UT, USA; Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, UT, USA
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29
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Frazer AK, Pearce AJ, Howatson G, Thomas K, Goodall S, Kidgell DJ. Determining the potential sites of neural adaptation to cross-education: implications for the cross-education of muscle strength. Eur J Appl Physiol 2018; 118:1751-1772. [PMID: 29995227 DOI: 10.1007/s00421-018-3937-5] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2018] [Accepted: 07/05/2018] [Indexed: 12/11/2022]
Abstract
Cross-education describes the strength gain in the opposite, untrained limb following a unilateral strength training program. Since its discovery in 1894, several studies now confirm the existence of cross-education in contexts that involve voluntary dynamic contractions, eccentric contraction, electrical stimulation, whole-body vibration and, more recently, following mirror feedback training. Although many aspects of cross-education have been established, the mediating neural mechanisms remain unclear. Overall, the findings of this review show that the neural adaptations to cross-education of muscle strength most likely represent a continuum of change within the central nervous system that involves both structural and functional changes within cortical motor and non-motor regions. Such changes are likely to be the result of more subtle changes along the entire neuroaxis which include, increased corticospinal excitability, reduced cortical inhibition, reduced interhemispheric inhibition, changes in voluntary activation and new regions of cortical activation. However, there is a need to widen the breadth of research by employing several neurophysiological techniques (together) to better understand the potential mechanisms mediating cross-education. This fundamental step is required in order to better prescribe targeted and effective guidelines for the clinical practice of cross-education. There is a need to determine whether similar cortical responses also occur in clinical populations where, perhaps, the benefits of cross-education could be best observed.
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Affiliation(s)
- Ashlyn K Frazer
- Department of Physiotherapy, Faculty of Medicine, Nursing and Health Sciences, School of Primary and Allied Health Care, Monash University, PO Box 527, Frankston, Melbourne, VIC, 3199, Australia.
| | - Alan J Pearce
- Discipline of Exercise Science, School of Allied Health, La Trobe University, Melbourne, Australia
| | - Glyn Howatson
- Department of Sport, Exercise and Rehabilitation, Northumbria University, Newcastle-upon-Tyne, UK.,Water Research Group, School of Biological Sciences, North West University, Potchefstroom, South Africa
| | - Kevin Thomas
- Department of Sport, Exercise and Rehabilitation, Northumbria University, Newcastle-upon-Tyne, UK
| | - Stuart Goodall
- Department of Sport, Exercise and Rehabilitation, Northumbria University, Newcastle-upon-Tyne, UK
| | - Dawson J Kidgell
- Department of Physiotherapy, Faculty of Medicine, Nursing and Health Sciences, School of Primary and Allied Health Care, Monash University, PO Box 527, Frankston, Melbourne, VIC, 3199, Australia
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