1
|
Walker S, Sahinaho UM, Vekki S, Sulonen M, Laukkanen JA, Sipilä S, Peltonen H, Laakkonen E, Lehti M. Two-week step-reduction has limited negative effects on physical function and metabolic health in older adults. Eur J Appl Physiol 2024; 124:2019-2033. [PMID: 38383794 PMCID: PMC11199225 DOI: 10.1007/s00421-024-05426-1] [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: 07/11/2023] [Accepted: 01/21/2024] [Indexed: 02/23/2024]
Abstract
PURPOSE This study determined the effects of a 2-week step-reduction period followed by 4-week exercise rehabilitation on physical function, body composition, and metabolic health in 70-80-year-olds asymptomatic for injury/illness. METHODS A parallel-group randomized controlled trial (ENDURE-study, NCT04997447) was used, where 66 older adults (79% female) were randomized to either intervention or control group. The intervention group reduced daily steps to < 2000, monitored by accelerometer, for two weeks (Period I) and then step-reduction requirement was removed with an additional exercise rehabilitation 4 times per week for 4 weeks (Period II). The control group continued their habitual physical activity throughout with no additional exercise intervention. Laboratory tests were performed at baseline, after Period I and Period II. The primary outcome measure was leg lean mass (LLM). Secondary outcomes included total lean and fat mass, blood glucose and insulin concentration, LDL cholesterol and HDL cholesterol concentration, maximal isometric leg press force (MVC), and chair rise and stair climb performance. RESULTS LLM remained unchanged in both groups and no changes occurred in physical function nor body composition in the intervention group in Period I. HDL cholesterol concentration reduced after Period I (from 1.62 ± 0.37 to 1.55 ± 0.36 mmol·L-1, P = 0.017) and returned to baseline after Period II (1.66 ± 0.38 mmol·L-1) in the intervention group (Time × Group interaction: P = 0.065). MVC improved after Period II only (Time × Group interaction: P = 0.009, Δ% = 15%, P < 0.001). CONCLUSION Short-term step-reduction in healthy older adults may not be as detrimental to health or physical function as currently thought.
Collapse
Affiliation(s)
- Simon Walker
- Faculty of Sport and Health Sciences, University of Jyväskylä, Room VIV225, 40014-FI, Jyväskylä, Finland.
- NeuroMuscular Research Center, University of Jyväskylä, Jyväskylä, Finland.
| | - Ulla-Maria Sahinaho
- Faculty of Sport and Health Sciences, University of Jyväskylä, Room VIV225, 40014-FI, Jyväskylä, Finland
| | - Sakari Vekki
- Faculty of Sport and Health Sciences, University of Jyväskylä, Room VIV225, 40014-FI, Jyväskylä, Finland
| | - Mari Sulonen
- Faculty of Sport and Health Sciences, University of Jyväskylä, Room VIV225, 40014-FI, Jyväskylä, Finland
| | - Jari A Laukkanen
- Institute of Clinical Medicine, Department of Medicine, University of Eastern Finland, Kuopio, Finland
- Department of Medicine, Wellbeing Services County of Central Finland, Jyväskylä, Finland
| | - Sarianna Sipilä
- Faculty of Sport and Health Sciences, University of Jyväskylä, Room VIV225, 40014-FI, Jyväskylä, Finland
- Gerontology Research Center, University of Jyväskylä, Jyväskylä, Finland
| | - Heikki Peltonen
- JAMK University of Applied Science, The School of Business, Sport Business, Jyväskylä, Finland
| | - Eija Laakkonen
- Faculty of Sport and Health Sciences, University of Jyväskylä, Room VIV225, 40014-FI, Jyväskylä, Finland
- Gerontology Research Center, University of Jyväskylä, Jyväskylä, Finland
| | - Maarit Lehti
- Faculty of Sport and Health Sciences, University of Jyväskylä, Room VIV225, 40014-FI, Jyväskylä, Finland
| |
Collapse
|
2
|
Deane C, Piasecki M, Atherton P. Skeletal muscle immobilisation-induced atrophy: mechanistic insights from human studies. Clin Sci (Lond) 2024; 138:741-756. [PMID: 38895777 PMCID: PMC11186857 DOI: 10.1042/cs20231198] [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: 02/16/2024] [Revised: 05/28/2024] [Accepted: 06/04/2024] [Indexed: 06/21/2024]
Abstract
Periods of skeletal muscle disuse lead to rapid declines in muscle mass (atrophy), which is fundamentally underpinned by an imbalance between muscle protein synthesis (MPS) and muscle protein breakdown (MPB). The complex interplay of molecular mechanisms contributing to the altered regulation of muscle protein balance during disuse have been investigated but rarely synthesised in the context of humans. This narrative review discusses human models of muscle disuse and the ensuing inversely exponential rate of muscle atrophy. The molecular processes contributing to altered protein balance are explored, with a particular focus on growth and breakdown signalling pathways, mitochondrial adaptations and neuromuscular dysfunction. Finally, key research gaps within the disuse atrophy literature are highlighted providing future avenues to enhance our mechanistic understanding of human disuse atrophy.
Collapse
Affiliation(s)
- Colleen S. Deane
- Human Development and Health, Faculty of Medicine, University of Southampton, Southampton General Hospital, U.K
| | - Matthew Piasecki
- Centre of Metabolism, Ageing and Physiology (CoMAP), Medical Research Council/Versus Arthritis UK Centre of Excellence for Musculoskeletal Ageing Research (CMAR), National Institute of Health Research (NIHR) Biomedical Research Centre (BRC), University of Nottingham, U.K
| | - Philip J. Atherton
- Centre of Metabolism, Ageing and Physiology (CoMAP), Medical Research Council/Versus Arthritis UK Centre of Excellence for Musculoskeletal Ageing Research (CMAR), National Institute of Health Research (NIHR) Biomedical Research Centre (BRC), University of Nottingham, U.K
| |
Collapse
|
3
|
Hughes AK, Francis T, Rooney J, Pollock R, Witard OC. The effect of protein or amino acid provision on immobilization-induced muscle atrophy in healthy adults: A systematic review and meta-analysis. Exp Physiol 2024; 109:873-888. [PMID: 38424716 PMCID: PMC11140175 DOI: 10.1113/ep090434] [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: 12/11/2023] [Accepted: 01/25/2024] [Indexed: 03/02/2024]
Abstract
Bed rest and limb immobilization are models of muscle disuse associated with skeletal muscle atrophy and reduced strength. The purpose of this systematic review was to examine the impact of protein or amino acid provision before and/or during a period of muscle disuse on muscle atrophy (primary outcome), strength and muscle protein synthesis (secondary outcomes) following a disuse period. We performed a systematic review of Embase, MEDLINE, Web of Science, PubMed and Clinical Trials in December 2022. Eligible studies were randomized controlled trials that combined a dietary protein or amino acid intervention versus control during an experimental model of disuse (bed rest or unilateral limb immobilization) in healthy individuals aged ≥18 years. Nine articles from eight independent trials were identified and rated for risk of bias by two authors. A meta-analysis of muscle mass data revealed no effect (standardized mean difference: 0.2; 95% confidence interval: -0.18 to 0.57, P = 0.31) of protein/amino acid intervention in preventing disuse-induced muscle atrophy. Although the meta-analysis was not conducted on strength or muscle protein synthesis data, there was insufficient evidence in the reviewed articles to support the use of protein/amino acid provision in mitigating the disuse-induced decline in either outcome measurement. Additional high-quality studies, including the reporting of randomization procedures and blinding procedures and the provision of statistical analysis plans, might be required to determine whether protein or amino acid provision serves as an effective strategy to attenuate muscle atrophy during periods of disuse.
Collapse
Affiliation(s)
- Alix K. Hughes
- Centre for Human and Applied Physiological SciencesKing's College LondonLondonUK
| | - Thomas Francis
- Centre for Human and Applied Physiological SciencesKing's College LondonLondonUK
| | - Jessica Rooney
- Centre for Human and Applied Physiological SciencesKing's College LondonLondonUK
| | - Ross Pollock
- Centre for Human and Applied Physiological SciencesKing's College LondonLondonUK
| | - Oliver C. Witard
- Centre for Human and Applied Physiological SciencesKing's College LondonLondonUK
| |
Collapse
|
4
|
Houben LHP, Tuytten T, Holwerda AM, Wisanto E, Senden J, Wodzig WKWH, Olde Damink SWM, Beelen M, Beijer S, VAN Renterghem K, VAN Loon LJC. A Low or High Physical Activity Level Does Not Modulate Prostate Tumor Tissue Protein Synthesis Rates. Med Sci Sports Exerc 2024; 56:635-643. [PMID: 38079310 DOI: 10.1249/mss.0000000000003349] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/16/2024]
Abstract
INTRODUCTION Physical activity level has been identified as an important factor in the development and progression of various types of cancer. In this study, we determined the impact of a low versus high physical activity level on skeletal muscle, healthy prostate, and prostate tumor protein synthesis rates in vivo in prostate cancer patients. METHODS Thirty prostate cancer patients (age, 66 ± 5 yr; body mass index, 27.4 ± 2.9 kg·m -2 ) were randomized to a low (<4000 steps per day, n = 15) or high (>14,000 steps per day, n = 15) physical activity level for 7 d before their scheduled radical prostatectomy. Daily deuterium oxide administration was combined with the collection of plasma, skeletal muscle, nontumorous prostate, and prostate tumor tissue during the surgical procedure to determine tissue protein synthesis rates throughout the intervention period. RESULTS Daily step counts averaged 3610 ± 878 and 17,589 ± 4680 steps in patients subjected to the low and high physical activity levels, respectively ( P < 0.001). No differences were observed between tissue protein synthesis rates of skeletal muscle, healthy prostate, or prostate tumor between the low (1.47% ± 0.21%, 2.74% ± 0.70%, and 4.76% ± 1.23% per day, respectively) and high (1.42% ± 0.16%, 2.64% ± 0.58%, and 4.72% ± 0.80% per day, respectively) physical activity group (all P > 0.4). Tissue protein synthesis rates were nearly twofold higher in prostate tumor compared with nontumorous prostate tissue. CONCLUSIONS A short-term high or low physical activity level does not modulate prostate or prostate tumor protein synthesis rates in vivo in prostate cancer patients. More studies on the impact of physical activity level on tumor protein synthesis rates and tumor progression are warranted to understand the potential impact of lifestyle interventions in the prevention and treatment of cancer.
Collapse
Affiliation(s)
| | - Tom Tuytten
- Department of Urology, Jessa Hospital, Hasselt, BELGIUM
| | - Andrew M Holwerda
- Department of Human Biology, NUTRIM School of Nutrition and Translational Research in Metabolism, Maastricht University Medical Centre+, Maastricht, THE NETHERLANDS
| | - Erika Wisanto
- Department of Pathology, Jessa Hospital, Hasselt, BELGIUM
| | - Joan Senden
- Department of Human Biology, NUTRIM School of Nutrition and Translational Research in Metabolism, Maastricht University Medical Centre+, Maastricht, THE NETHERLANDS
| | - Will K W H Wodzig
- Central Diagnostic Laboratory, Maastricht University Medical Centre+, Maastricht, THE NETHERLANDS
| | | | | | | | | | | |
Collapse
|
5
|
Fuchs CJ, Hermans WJH, Nyakayiru J, Weijzen MEG, Smeets JSJ, Aussieker T, Senden JM, Wodzig WKHW, Snijders T, Verdijk LB, van Loon LJC. Daily blood flow restriction does not preserve muscle mass and strength during 2 weeks of bed rest. J Physiol 2024. [PMID: 38411283 DOI: 10.1113/jp286065] [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: 11/29/2023] [Accepted: 02/08/2024] [Indexed: 02/28/2024] Open
Abstract
We measured the impact of blood flow restriction on muscle protein synthesis rates, muscle mass and strength during 2 weeks of strict bed rest. Twelve healthy, male adults (age: 24 ± 3 years, body mass index: 23.7 ± 3.1 kg/m2 ) were subjected to 14 days of strict bed rest with unilateral blood flow restriction performed three times daily in three 5 min cycles (200 mmHg). Participants consumed deuterium oxide and we collected blood and saliva samples throughout 2 weeks of bed rest. Before and immediately after bed rest, lean body mass (dual-energy X-ray absorptiometry scan) and thigh muscle volume (magnetic resonance imaging scan) were assessed in both the blood flow restricted (BFR) and control (CON) leg. Muscle biopsies were collected and unilateral muscle strength (one-repetition maximum; 1RM) was assessed for both legs before and after the bed rest period. Bed rest resulted in 1.8 ± 1.0 kg lean body mass loss (P < 0.001). Thigh muscle volume declined from 7.1 ± 1.1 to 6.7 ± 1.0 L in CON and from 7.0 ± 1.1 to 6.7 ± 1.0 L in BFR (P < 0.001), with no differences between treatments (P = 0.497). In addition, 1RM leg extension strength decreased from 60.2 ± 10.6 to 54.8 ± 10.9 kg in CON and from 59.2 ± 12.1 to 52.9 ± 12.0 kg in BFR (P = 0.014), with no differences between treatments (P = 0.594). Muscle protein synthesis rates during bed rest did not differ between the BFR and CON leg (1.11 ± 0.12 vs. 1.08 ± 0.13%/day, respectively; P = 0.302). Two weeks of bed rest substantially reduces skeletal muscle mass and strength. Blood flow restriction during bed rest does not modulate daily muscle protein synthesis rates and does not preserve muscle mass or strength. KEY POINTS: Bed rest, often necessary for recovery from illness or injury, leads to the loss of muscle mass and strength. It has been postulated that blood flow restriction may attenuate the loss of muscle mass and strength during bed rest. We investigated the effect of blood flow restriction on muscle protein synthesis rates, muscle mass and strength during 2 weeks of strict bed rest. Blood flow restriction applied during bed rest does not modulate daily muscle protein synthesis rates and does not preserve muscle mass or strength. Blood flow restriction is not effective in preventing muscle atrophy during a prolonged period of bed rest.
Collapse
Affiliation(s)
- Cas J Fuchs
- Department of Human Biology, Faculty of Health, Medicine and Life Sciences, School of Nutrition and Translational Research in Metabolism (NUTRIM), Maastricht University Medical Centre+, Maastricht, The Netherlands
| | - Wesley J H Hermans
- Department of Human Biology, Faculty of Health, Medicine and Life Sciences, School of Nutrition and Translational Research in Metabolism (NUTRIM), Maastricht University Medical Centre+, Maastricht, The Netherlands
| | - Jean Nyakayiru
- Department of Human Biology, Faculty of Health, Medicine and Life Sciences, School of Nutrition and Translational Research in Metabolism (NUTRIM), Maastricht University Medical Centre+, Maastricht, The Netherlands
| | - Michelle E G Weijzen
- Department of Human Biology, Faculty of Health, Medicine and Life Sciences, School of Nutrition and Translational Research in Metabolism (NUTRIM), Maastricht University Medical Centre+, Maastricht, The Netherlands
| | - Joey S J Smeets
- Department of Human Biology, Faculty of Health, Medicine and Life Sciences, School of Nutrition and Translational Research in Metabolism (NUTRIM), Maastricht University Medical Centre+, Maastricht, The Netherlands
| | - Thorben Aussieker
- Department of Human Biology, Faculty of Health, Medicine and Life Sciences, School of Nutrition and Translational Research in Metabolism (NUTRIM), Maastricht University Medical Centre+, Maastricht, The Netherlands
| | - Joan M Senden
- Department of Human Biology, Faculty of Health, Medicine and Life Sciences, School of Nutrition and Translational Research in Metabolism (NUTRIM), Maastricht University Medical Centre+, Maastricht, The Netherlands
| | - Will K H W Wodzig
- Central Diagnostic Laboratory, Maastricht University Medical Centre+, Maastricht, The Netherlands
| | - Tim Snijders
- Department of Human Biology, Faculty of Health, Medicine and Life Sciences, School of Nutrition and Translational Research in Metabolism (NUTRIM), Maastricht University Medical Centre+, Maastricht, The Netherlands
| | - Lex B Verdijk
- Department of Human Biology, Faculty of Health, Medicine and Life Sciences, School of Nutrition and Translational Research in Metabolism (NUTRIM), Maastricht University Medical Centre+, Maastricht, The Netherlands
| | - Luc J C van Loon
- Department of Human Biology, Faculty of Health, Medicine and Life Sciences, School of Nutrition and Translational Research in Metabolism (NUTRIM), Maastricht University Medical Centre+, Maastricht, The Netherlands
| |
Collapse
|
6
|
Smeuninx B, Elhassan YS, Sapey E, Rushton AB, Morgan PT, Korzepa M, Belfield AE, Philp A, Brook MS, Gharahdaghi N, Wilkinson D, Smith K, Atherton PJ, Breen L. A single bout of prior resistance exercise attenuates muscle atrophy and declines in myofibrillar protein synthesis during bed-rest in older men. J Physiol 2023. [PMID: 37856286 DOI: 10.1113/jp285130] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2023] [Accepted: 10/05/2023] [Indexed: 10/21/2023] Open
Abstract
Impairments in myofibrillar protein synthesis (MyoPS) during bed rest accelerate skeletal muscle loss in older adults, increasing the risk of adverse secondary health outcomes. We investigated the effect of prior resistance exercise (RE) on MyoPS and muscle morphology during a disuse event in 10 healthy older men (65-80 years). Participants completed a single bout of unilateral leg RE the evening prior to 5 days of in-patient bed-rest. Quadriceps cross-sectional area (CSA) was determined prior to and following bed-rest. Serial muscle biopsies and dual stable isotope tracers were used to determine rates of integrated MyoPS (iMyoPS) over a 7 day habitual 'free-living' phase and the bed-rest phase, and rates of acute postabsorptive and postprandial MyoPS (aMyoPS) at the end of bed rest. Quadriceps CSA at 40%, 60% and 80% of muscle length significantly decreased in exercised (EX) and non-exercised control (CTL) legs with bed-rest. The decline in quadriceps CSA at 40% and 60% of muscle length was attenuated in EX compared with CTL. During bed-rest, iMyoPS rates decreased from habitual values in CTL, but not EX, and were significantly different between legs. Postprandial aMyoPS rates increased above postabsorptive values in EX only. The change in iMyoPS over bed-rest correlated with the change in quadriceps CSA in CTL, but not EX. A single bout of RE attenuated the decline in iMyoPS rates and quadriceps atrophy with 5 days of bed-rest in older men. Further work is required to understand the functional and clinical implications of prior RE in older patient populations. KEY POINTS: Age-related skeletal muscle deterioration, linked to numerous adverse health outcomes, is driven by impairments in muscle protein synthesis that are accelerated during periods of disuse. Resistance exercise can stimulate muscle protein synthesis over several days of recovery and therefore could counteract impairments in this process that occur in the early phase of disuse. In the present study, we demonstrate that the decline in myofibrillar protein synthesis and muscle atrophy over 5 days of bed-rest in older men was attenuated by a single bout of unilateral resistance exercise performed the evening prior to bed-rest. These findings suggest that concise resistance exercise intervention holds the potential to support muscle mass retention in older individuals during short-term disuse, with implications for delaying sarcopenia progression in ageing populations.
Collapse
Affiliation(s)
- Benoit Smeuninx
- School of Sport, Exercise and Rehabilitation Sciences, University of Birmingham, Birmingham, UK
- Cellular & Molecular Metabolism Laboratory, Monash University, Melbourne, Victoria, Australia
| | - Yasir S Elhassan
- Institute of Metabolism and Systems Research, University of Birmingham, Birmingham, UK
- Centre for Endocrinology, Diabetes and Metabolism, Birmingham Health Partners, Birmingham, UK
| | - Elizabeth Sapey
- Birmingham Acute Care Research Group, Institute of Inflammation and Ageing, University of Birmingham, Birmingham, UK
| | - Alison B Rushton
- School of Sport, Exercise and Rehabilitation Sciences, University of Birmingham, Birmingham, UK
| | - Paul T Morgan
- School of Sport, Exercise and Rehabilitation Sciences, University of Birmingham, Birmingham, UK
| | - Marie Korzepa
- School of Sport, Exercise and Rehabilitation Sciences, University of Birmingham, Birmingham, UK
| | - Archie E Belfield
- School of Sport, Exercise and Rehabilitation Sciences, University of Birmingham, Birmingham, UK
| | - Andrew Philp
- Centre for Healthy Ageing, Centenary Institute, Camperdown, New South Wales, Australia
| | - Matthew S Brook
- Centre Of Metabolism, Ageing and Physiology (COMAP), School of Medicine, University of Nottingham, Royal Derby Hospital Centre, Derby, UK
- MRC-ARUK Centre of Excellence for Musculoskeletal Ageing Research, University of Nottingham, Derby, UK
| | - Nima Gharahdaghi
- Centre Of Metabolism, Ageing and Physiology (COMAP), School of Medicine, University of Nottingham, Royal Derby Hospital Centre, Derby, UK
- MRC-ARUK Centre of Excellence for Musculoskeletal Ageing Research, University of Nottingham, Derby, UK
| | - Daniel Wilkinson
- Centre Of Metabolism, Ageing and Physiology (COMAP), School of Medicine, University of Nottingham, Royal Derby Hospital Centre, Derby, UK
- MRC-ARUK Centre of Excellence for Musculoskeletal Ageing Research, University of Nottingham, Derby, UK
| | - Kenneth Smith
- Centre Of Metabolism, Ageing and Physiology (COMAP), School of Medicine, University of Nottingham, Royal Derby Hospital Centre, Derby, UK
- MRC-ARUK Centre of Excellence for Musculoskeletal Ageing Research, University of Nottingham, Derby, UK
| | - Philip J Atherton
- Centre Of Metabolism, Ageing and Physiology (COMAP), School of Medicine, University of Nottingham, Royal Derby Hospital Centre, Derby, UK
- MRC-ARUK Centre of Excellence for Musculoskeletal Ageing Research, University of Nottingham, Derby, UK
| | - Leigh Breen
- School of Sport, Exercise and Rehabilitation Sciences, University of Birmingham, Birmingham, UK
- MRC-ARUK Centre for Musculoskeletal Ageing Research, University of Birmingham, Birmingham, UK
- NIHR Birmingham Biomedical Research Centre, University Hospitals Birmingham NHS Foundation Trust and University of Birmingham, Birmingham, UK
| |
Collapse
|
7
|
Pinto AJ, Bergouignan A, Dempsey PC, Roschel H, Owen N, Gualano B, Dunstan DW. Physiology of sedentary behavior. Physiol Rev 2023; 103:2561-2622. [PMID: 37326297 PMCID: PMC10625842 DOI: 10.1152/physrev.00022.2022] [Citation(s) in RCA: 32] [Impact Index Per Article: 32.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2022] [Revised: 05/10/2023] [Accepted: 06/14/2023] [Indexed: 06/17/2023] Open
Abstract
Sedentary behaviors (SB) are characterized by low energy expenditure while in a sitting or reclining posture. Evidence relevant to understanding the physiology of SB can be derived from studies employing several experimental models: bed rest, immobilization, reduced step count, and reducing/interrupting prolonged SB. We examine the relevant physiological evidence relating to body weight and energy balance, intermediary metabolism, cardiovascular and respiratory systems, the musculoskeletal system, the central nervous system, and immunity and inflammatory responses. Excessive and prolonged SB can lead to insulin resistance, vascular dysfunction, shift in substrate use toward carbohydrate oxidation, shift in muscle fiber from oxidative to glycolytic type, reduced cardiorespiratory fitness, loss of muscle mass and strength and bone mass, and increased total body fat mass and visceral fat depot, blood lipid concentrations, and inflammation. Despite marked differences across individual studies, longer term interventions aimed at reducing/interrupting SB have resulted in small, albeit marginally clinically meaningful, benefits on body weight, waist circumference, percent body fat, fasting glucose, insulin, HbA1c and HDL concentrations, systolic blood pressure, and vascular function in adults and older adults. There is more limited evidence for other health-related outcomes and physiological systems and for children and adolescents. Future research should focus on the investigation of molecular and cellular mechanisms underpinning adaptations to increasing and reducing/interrupting SB and the necessary changes in SB and physical activity to impact physiological systems and overall health in diverse population groups.
Collapse
Affiliation(s)
- Ana J Pinto
- Division of Endocrinology, Metabolism, and Diabetes, Anschutz Health and Wellness Center, University of Colorado Anschutz Medical Campus, Aurora, Colorado, United States
- Applied Physiology & Nutrition Research Group, Center of Lifestyle Medicine, Faculdade de Medicina FMUSP, Universidade de Sao Paulo, Sao Paulo, Brazil
| | - Audrey Bergouignan
- Division of Endocrinology, Metabolism, and Diabetes, Anschutz Health and Wellness Center, University of Colorado Anschutz Medical Campus, Aurora, Colorado, United States
- Institut Pluridisciplinaire Hubert Curien, Centre National de la Recherche Scientifique, Université de Strasbourg, Strasbourg, France
| | - Paddy C Dempsey
- Baker Heart & Diabetes Institute, Melbourne, Victoria, Australia
- Institute for Physical Activity and Nutrition (IPAN), School of Exercise and Nutrition Sciences, Deakin University, Geelong, Victoria, Australia
- MRC Epidemiology Unit, Institute of Metabolic Science, University of Cambridge, Cambridge Biomedical Campus, Cambridge, United Kingdom
- Diabetes Research Centre, College of Life Sciences, University of Leicester, Leicester, United Kingdom
| | - Hamilton Roschel
- Applied Physiology & Nutrition Research Group, Center of Lifestyle Medicine, Faculdade de Medicina FMUSP, Universidade de Sao Paulo, Sao Paulo, Brazil
| | - Neville Owen
- Baker Heart & Diabetes Institute, Melbourne, Victoria, Australia
- Centre for Urban Transitions, Swinburne University of Technology, Melbourne, Victoria, Australia
| | - Bruno Gualano
- Applied Physiology & Nutrition Research Group, Center of Lifestyle Medicine, Faculdade de Medicina FMUSP, Universidade de Sao Paulo, Sao Paulo, Brazil
- Food Research Center, University of Sao Paulo, Sao Paulo, Brazil
| | - David W Dunstan
- Baker Heart & Diabetes Institute, Melbourne, Victoria, Australia
- Institute for Physical Activity and Nutrition (IPAN), School of Exercise and Nutrition Sciences, Deakin University, Geelong, Victoria, Australia
| |
Collapse
|
8
|
Changes in the Mechanical Properties of Fast and Slow Skeletal Muscle after 7 and 21 Days of Restricted Activity in Rats. Int J Mol Sci 2023; 24:ijms24044141. [PMID: 36835551 PMCID: PMC9966780 DOI: 10.3390/ijms24044141] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2023] [Revised: 02/13/2023] [Accepted: 02/16/2023] [Indexed: 02/22/2023] Open
Abstract
Disuse muscle atrophy is usually accompanied by changes in skeletal muscle structure, signaling, and contractile potential. Different models of muscle unloading can provide valuable information, but the protocols of experiments with complete immobilization are not physiologically representative of a sedentary lifestyle, which is highly prevalent among humans now. In the current study, we investigated the potential effects of restricted activity on the mechanical characteristics of rat postural (soleus) and locomotor (extensor digitorum longus, EDL) muscles. The restricted-activity rats were kept in small Plexiglas cages (17.0 × 9.6 × 13.0 cm) for 7 and 21 days. After this, soleus and EDL muscles were collected for ex vivo mechanical measurements and biochemical analysis. We demonstrated that while a 21-day movement restriction affected the weight of both muscles, in soleus muscle we observed a greater decrease. The maximum isometric force and passive tension in both muscles also significantly changed after 21 days of movement restriction, along with a decrease in the level of collagen 1 and 3 mRNA expression. Furthermore, the collagen content itself changed only in soleus after 7 and 21 days of movement restriction. With regard to cytoskeletal proteins, in our experiment we observed a significant decrease in telethonin in soleus, and a similar decrease in desmin and telethonin in EDL. We also observed a shift towards fast-type myosin heavy chain expression in soleus, but not in EDL. In summary, in this study we showed that movement restriction leads to profound specific changes in the mechanical properties of fast and slow skeletal muscles. Future studies may include evaluation of signaling mechanisms regulating the synthesis, degradation, and mRNA expression of the extracellular matrix and scaffold proteins of myofibers.
Collapse
|
9
|
Magkos F, Reeds DN, Mittendorfer B. Evolution of the diagnostic value of "the sugar of the blood": hitting the sweet spot to identify alterations in glucose dynamics. Physiol Rev 2023; 103:7-30. [PMID: 35635320 PMCID: PMC9576168 DOI: 10.1152/physrev.00015.2022] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2022] [Revised: 05/23/2022] [Accepted: 05/24/2022] [Indexed: 11/22/2022] Open
Abstract
In this paper, we provide an overview of the evolution of the definition of hyperglycemia during the past century and the alterations in glucose dynamics that cause fasting and postprandial hyperglycemia. We discuss how extensive mechanistic, physiological research into the factors and pathways that regulate the appearance of glucose in the circulation and its uptake and metabolism by tissues and organs has contributed knowledge that has advanced our understanding of different types of hyperglycemia, namely prediabetes and diabetes and their subtypes (impaired fasting plasma glucose, impaired glucose tolerance, combined impaired fasting plasma glucose, impaired glucose tolerance, type 1 diabetes, type 2 diabetes, gestational diabetes mellitus), their relationships with medical complications, and how to prevent and treat hyperglycemia.
Collapse
Affiliation(s)
- Faidon Magkos
- Department of Nutrition, Exercise and Sports, University of Copenhagen, Frederiksberg, Denmark
| | - Dominic N Reeds
- Center for Human Nutrition, Washington University School of Medicine, St. Louis, Missouri
| | - Bettina Mittendorfer
- Center for Human Nutrition, Washington University School of Medicine, St. Louis, Missouri
| |
Collapse
|
10
|
Moore DR, Williamson EP, Hodson N, Estafanos S, Mazzulla M, Kumbhare D, Gillen JB. Walking or body weight squat 'activity snacks' increase dietary amino acid utilization for myofibrillar protein synthesis during prolonged sitting. J Appl Physiol (1985) 2022; 133:777-785. [PMID: 35952344 DOI: 10.1152/japplphysiol.00106.2022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Interrupting prolonged sitting with intermittent exercise enhances postprandial glycemic control but has unknown effects on sensitizing skeletal muscle to dietary amino acids. We hypothesized that brief walking or body weight squats would enhance the utilization of dietary phenylalanine for myofibrillar protein synthesis (MyoPS) during prolonged sitting. Participants (7 males and 5 females; ~23y; ~25.1kg/m2; ~7300 steps/d) completed three 7.5h trials consisting of prolonged sitting (SIT) or sitting with intermittent (every 30 minutes) walking (WALK) or body weight squatting (SQUAT). Two mixed-macronutrient meals (~55:30:15% carbohydrate:fat:protein), enriched with L-[ring-2H5]phenylalanine or L-[ring-13C6]phenylalanine, were provided to mimic breakfast and lunch. Tracer incorporation into myofibrillar protein was determined from the vastus lateralis with MyoPS estimated using plasma enrichment as precursor surrogate. Phosphorylation of candidate anabolic signaling proteins were determined by immunoblotting. There was no difference between conditions (p≥0.78) in the time course or area under the curve for plasma phenylalanine enrichment. MyoPS was greater (p<0.05, weighted planned comparison) in SQUAT (0.103±0.030%/h) and WALK (0.118±0.037%/h) compared to SIT (0.080±0.032%/h). Compared to SIT, there were moderate-to-large effect sizes, respectively, for SQUAT (ES=0.75; 95% CI -0.10-1.55) and WALK (ES=1.10; 95% CI 0.20-1.91). Fold change in rpS6Ser240/244 phosphorylation was greater in SQUAT compared to SIT (7.6±2.7 vs. 1.6±0.45 fold, p<0.05) with no difference (p≥0.21) in any other targets measured (4E-BP1Thr37/46, eEF2Thr56, mTORSer2448, ERK1/2Thr202/Tyr204). Interrupting prolonged sitting with short 'activity snacks' improves the utilization of dietary amino acids for MyoPS. The long term impact of this practical lifestyle modification for muscle mass or quality should be investigated.
Collapse
Affiliation(s)
- Daniel R Moore
- Faculty of Kinesiology and Physical Education, University of Toronto, Toronto, ON, Canada
| | - Eric P Williamson
- Faculty of Kinesiology and Physical Education, University of Toronto, Toronto, ON, Canada
| | - Nathan Hodson
- Faculty of Kinesiology and Physical Education, University of Toronto, Toronto, ON, Canada
| | - Stephanie Estafanos
- Faculty of Kinesiology and Physical Education, University of Toronto, Toronto, ON, Canada
| | - Michael Mazzulla
- Faculty of Kinesiology and Physical Education, University of Toronto, Toronto, ON, Canada
| | | | - Jenna B Gillen
- Faculty of Kinesiology and Physical Education, University of Toronto, Toronto, ON, Canada
| |
Collapse
|
11
|
The Impact of Online-Schooling during COVID-19 on Device-Measured 24-Hour Movement Behaviours among High School Students: A Compositional Data Analysis. CHILDREN 2022; 9:children9050667. [PMID: 35626844 PMCID: PMC9139799 DOI: 10.3390/children9050667] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/05/2022] [Revised: 04/26/2022] [Accepted: 04/29/2022] [Indexed: 11/29/2022]
Abstract
The COVID-19 measures have unfavourably affected the movement behaviours of youth. The aim of this study was to explore the impact of online-schooling during COVID-19 on device-measured sleep (SL), sedentary behaviour (SB), light physical activity (LPA), and moderate–vigorous physical activity (MVPA) among high school students. A total of 51 students (26 female) from Slovenia wore an activity monitor activPAL4 during the weekdays of onsite-schooling and during the weekdays of online-schooling. Data on movement behaviours were analysed using compositional data analysis. During the onsite-schooling (and online-schooling), students spent on average 432 min/day (469 min/day) in SL, 731 (755) in SB, 253 (202) in LPA, and 25 (15) in MVPA. Repeated measures multivariate analysis of variance confirmed significantly more time was spent in SL (log ratio 0.29; 95% CI 0.20, 0.37)) and SB (log ratio 0.23; 95% CI 0.13, 0.32) and less time in MVPA (log ratio −0.44; 95% CI −0.66, −0.23) during the online-schooling weekdays. Students spent significantly more time in SB during leisure (log ratio 0.20; 95% CI 0.06, 0.35) as well as during lecture time (log ratio 0.45; 95% CI 0.32, 0.58). Our results indicate that online-schooling significantly contributed to the unfavourable changes in students’ movement behaviours during COVID-19. Future studies should focus on developing physical activity interventions suitable for the circumstances of the epidemic.
Collapse
|
12
|
Sharlo K, Tyganov SA, Tomilovskaya E, Popov DV, Saveko AA, Shenkman BS. Effects of Various Muscle Disuse States and Countermeasures on Muscle Molecular Signaling. Int J Mol Sci 2021; 23:ijms23010468. [PMID: 35008893 PMCID: PMC8745071 DOI: 10.3390/ijms23010468] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2021] [Revised: 12/24/2021] [Accepted: 12/30/2021] [Indexed: 12/17/2022] Open
Abstract
Skeletal muscle is capable of changing its structural parameters, metabolic rate and functional characteristics within a wide range when adapting to various loading regimens and states of the organism. Prolonged muscle inactivation leads to serious negative consequences that affect the quality of life and work capacity of people. This review examines various conditions that lead to decreased levels of muscle loading and activity and describes the key molecular mechanisms of muscle responses to these conditions. It also details the theoretical foundations of various methods preventing adverse muscle changes caused by decreased motor activity and describes these methods. A number of recent studies presented in this review make it possible to determine the molecular basis of the countermeasure methods used in rehabilitation and space medicine for many years, as well as to identify promising new approaches to rehabilitation and to form a holistic understanding of the mechanisms of gravity force control over the muscular system.
Collapse
|
13
|
Edwards SJ, Shad BJ, Marshall RN, Morgan PT, Wallis GA, Breen L. Short-term step reduction reduces CS activity without altering skeletal muscle markers of oxidative metabolism or insulin-mediated signalling in young males. J Appl Physiol (1985) 2021; 131:1653-1662. [PMID: 34734783 PMCID: PMC8714983 DOI: 10.1152/japplphysiol.00650.2021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Mitochondria are critical to skeletal muscle contractile function and metabolic health. Short-term periods of step reduction (SR) are associated with alterations in muscle protein turnover and mass. However, the effects of SR on mitochondrial metabolism/muscle oxidative metabolism and insulin-mediated signaling are unclear. We tested the hypothesis that the total and/or phosphorylated protein content of key skeletal muscle markers of mitochondrial/oxidative metabolism, and insulin-mediated signaling would be altered over 7 days of SR in young healthy males. Eleven, healthy, recreationally active males (means ± SE, age: 22 ± 1 yr, BMI: 23.4 ± 0.7 kg·m2) underwent a 7-day period of SR. Immediately before and following SR, fasted-state muscle biopsy samples were acquired and analyzed for the assessment of total and phosphorylated protein content of key markers of mitochondrial/oxidative metabolism and insulin-mediated signaling. Daily step count was significantly reduced during the SR intervention (13,054 ± 833 to 1,192 ± 99 steps·day−1, P < 0.001). Following SR, there was a significant decline in maximal citrate synthase activity (fold change: 0.94 ± 0.08, P < 0.05) and a significant increase in the protein content of p-glycogen synthase (P-GSS641; fold change: 1.47 ± 0.14, P < 0.05). No significant differences were observed in the total or phosphorylated protein content of other key markers of insulin-mediated signaling, oxidative metabolism, mitochondrial function, or mitochondrial dynamics (all P > 0.05). These results suggest that short-term SR reduces the maximal activity of citrate synthase, a marker of mitochondrial content, without altering the total or phosphorylated protein content of key markers of skeletal muscle mitochondrial metabolism and insulin signaling in young healthy males. NEW & NOTEWORTHY Short-term (7 day) step reduction reduces the activity of citrate synthase without altering the total or phosphorylated protein content of key markers of skeletal muscle mitochondrial metabolism and insulin signaling in young healthy males.
Collapse
Affiliation(s)
- Sophie J Edwards
- School of Sport, Exercise and Rehabilitation Sciences, University of Birmingham, Birmingham, United Kingdom
| | - Brandon J Shad
- School of Sport, Exercise and Rehabilitation Sciences, University of Birmingham, Birmingham, United Kingdom
| | - Ryan N Marshall
- School of Sport, Exercise and Rehabilitation Sciences, University of Birmingham, Birmingham, United Kingdom.,MRC-ARUK Centre for Musculoskeletal Ageing Research, University of Birmingham, United Kingdom
| | - Paul T Morgan
- School of Sport, Exercise and Rehabilitation Sciences, University of Birmingham, Birmingham, United Kingdom
| | - Gareth Anthony Wallis
- School of Sport, Exercise and Rehabilitation Sciences, University of Birmingham, Birmingham, United Kingdom
| | - Leigh Breen
- School of Sport, Exercise and Rehabilitation Sciences, University of Birmingham, Birmingham, United Kingdom.,MRC-ARUK Centre for Musculoskeletal Ageing Research, University of Birmingham, United Kingdom
| |
Collapse
|
14
|
Abou Sawan S, Hodson N, Tinline-Goodfellow C, West DWD, Malowany JM, Kumbhare D, Moore DR. Incorporation of Dietary Amino Acids Into Myofibrillar and Sarcoplasmic Proteins in Free-Living Adults Is Influenced by Sex, Resistance Exercise, and Training Status. J Nutr 2021; 151:3350-3360. [PMID: 34486662 DOI: 10.1093/jn/nxab261] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2021] [Revised: 06/25/2021] [Accepted: 07/15/2021] [Indexed: 12/24/2022] Open
Abstract
BACKGROUND Acute exercise increases the incorporation of dietary amino acids into de novo myofibrillar proteins after a single meal in controlled laboratory studies in males. It is unclear whether this extends to free-living settings or is influenced by training or sex. OBJECTIVES We determined the effects of exercise, training status, and sex on 24-hour free-living dietary phenylalanine incorporation into skeletal muscle proteins. METHODS In a parallel group design, recreationally active males (mean ± SD age, 23 ± 3 years; BMI. 23.4 ± 2.9 kg/m2; n = 10) and females (age 24 ± 5 years; BMI, 23.1 ± 3.9 kg/m2; n = 9) underwent 8 weeks of whole-body resistance exercise 3 times a week. Controlled diets containing 1.6 g/kg-1/d-1 (amino acids modelled after egg), enriched to 10% with [13C6] or [2H5]phenylalanine, were consumed before and after an acute bout of resistance exercise. Fasted muscle biopsies were obtained before [untrained, pre-exercise condition (REST ] and 24 hours after an acute bout of resistance exercise in untrained (UT) and trained (T) states to determine dietary phenylalanine incorporation into myofibrillar (ΔMyo) and sarcoplasmic (ΔSarc) proteins, intracellular mechanistic target of rapamycin (mTOR) colocalization with ulex europaeus agglutinin-1 (UEA-1; capillary marker; immunofluorescence), and amino acid transporter expression (Western blotting). RESULTS The ΔMyo values were ∼62% greater (P < 0.01) in females than males at REST. The ΔMyo values increased above REST by ∼51% during UT and ∼30% in T (both P < 0.01) in males, remained unchanged in females during UT, and were ∼33% lower at T when compared to UT (P = 0.013). Irrespective of sex, ΔMyo and ΔSarc were decreased at T compared to UT (P ≤ 0.026). Resistance training increased mTOR colocalization with UEA-1 (P = 0.004), while L amino acid transporter 1, which was greater in males (P < 0.01), and sodium-coupled neutral amino acid transporter 2 protein expression were not affected by acute exercise (P ≥ 0.33) or training (P ≥ 0.45). CONCLUSIONS The exercise-induced incorporation of dietary phenylalanine into myofibrillar and sarcoplasmic proteins is attenuated after training regardless of sex, suggesting a reduced reliance on dietary amino acids for postexercise skeletal muscle remodeling in the T state.
Collapse
Affiliation(s)
- Sidney Abou Sawan
- Faculty of Kinesiology and Physical Education, University of Toronto, Toronto, Ontario, Canada
| | - Nathan Hodson
- Faculty of Kinesiology and Physical Education, University of Toronto, Toronto, Ontario, Canada
| | | | - Daniel W D West
- Faculty of Kinesiology and Physical Education, University of Toronto, Toronto, Ontario, Canada.,Toronto Rehabilitation Institute, Toronto, Canada
| | - Julia M Malowany
- Faculty of Kinesiology and Physical Education, University of Toronto, Toronto, Ontario, Canada
| | | | - Daniel R Moore
- Faculty of Kinesiology and Physical Education, University of Toronto, Toronto, Ontario, Canada
| |
Collapse
|
15
|
Jameson TSO, Kilroe SP, Fulford J, Abdelrahman DR, Murton AJ, Dirks ML, Stephens FB, Wall BT. Muscle damaging eccentric exercise attenuates disuse-induced declines in daily myofibrillar protein synthesis and transiently prevents muscle atrophy in healthy men. Am J Physiol Endocrinol Metab 2021; 321:E674-E688. [PMID: 34632796 PMCID: PMC8791791 DOI: 10.1152/ajpendo.00294.2021] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Short-term disuse leads to muscle loss driven by lowered daily myofibrillar protein synthesis (MyoPS). However, disuse commonly results from muscle damage, and its influence on muscle deconditioning during disuse is unknown. Twenty-one males [20 ± 1 yr, BMI = 24 ± 1 kg·m-2 (± SE)] underwent 7 days of unilateral leg immobilization immediately preceded by 300 bilateral, maximal, muscle-damaging eccentric quadriceps contractions (DAM; subjects n = 10) or no exercise (CON; subjects n = 11). Participants ingested deuterated water and underwent temporal bilateral thigh MRI scans and vastus lateralis muscle biopsies of immobilized (IMM) and nonimmobilized (N-IMM) legs. N-IMM quadriceps muscle volume remained unchanged throughout both groups. IMM quadriceps muscle volume declined after 2 days by 1.7 ± 0.5% in CON (P = 0.031; and by 1.3 ± 0.6% when corrected to N-IMM; P = 0.06) but did not change in DAM, and declined equivalently in CON [by 6.4 ± 1.1% (5.0 ± 1.6% when corrected to N-IMM)] and DAM [by 2.6 ± 1.8% (4.0 ± 1.9% when corrected to N-IMM)] after 7 days. Immobilization began to decrease MyoPS compared with N-IMM in both groups after 2 days (P = 0.109), albeit with higher MyoPS rates in DAM compared with CON (P = 0.035). Frank suppression of MyoPS was observed between days 2 and 7 in CON (IMM = 1.04 ± 0.12, N-IMM = 1.86 ± 0.10%·day-1; P = 0.002) but not DAM (IMM = 1.49 ± 0.29, N-IMM = 1.90 ± 0.30%·day-1; P > 0.05). Declines in MyoPS and quadriceps volume after 7 days correlated positively in CON (r2 = 0.403; P = 0.035) but negatively in DAM (r2 = 0.483; P = 0.037). Quadriceps strength declined following immobilization in both groups, but to a greater extent in DAM. Prior muscle-damaging eccentric exercise increases MyoPS and prevents loss of quadriceps muscle volume after 2 (but not 7) days of disuse.NEW & NOTEWORTHY We investigated the impact of prior muscle-damaging eccentric exercise on disuse-induced muscle deconditioning. Two and 7 days of muscle disuse per se lowered quadriceps muscle volume in association with lowered daily myofibrillar protein synthesis (MyoPS). Prior eccentric exercise prevented the decline in muscle volume after 2 days and attenuated the decline in MyoPS after 2 and 7 days. These data indicate eccentric exercise increases MyoPS and transiently prevents quadriceps muscle atrophy during muscle disuse.
Collapse
Affiliation(s)
- Tom S O Jameson
- Nutritional Physiology Group, Department of Sport and Health Sciences, College of Life and Environmental Sciences, University of Exeter, Exeter, United Kingdom
| | - Sean P Kilroe
- Department of Nutrition and Metabolism, Center for Recovery, Physical Activity and Nutrition, University of Texas Medical Branch, Galveston, Texas
| | - Jonathan Fulford
- Peninsula NIHR Clinical Research Facility, College of Medicine and Health, University of Exeter, Exeter, United Kingdom
| | - Doaa R Abdelrahman
- Department of Surgery, University of Texas Medical Branch, Galveston, Texas
| | - Andrew J Murton
- Department of Surgery, University of Texas Medical Branch, Galveston, Texas
- Sealy Center of Aging, University of Texas Medical Branch, Galveston, Texas
| | - Marlou L Dirks
- Nutritional Physiology Group, Department of Sport and Health Sciences, College of Life and Environmental Sciences, University of Exeter, Exeter, United Kingdom
| | - Francis B Stephens
- Nutritional Physiology Group, Department of Sport and Health Sciences, College of Life and Environmental Sciences, University of Exeter, Exeter, United Kingdom
| | - Benjamin T Wall
- Nutritional Physiology Group, Department of Sport and Health Sciences, College of Life and Environmental Sciences, University of Exeter, Exeter, United Kingdom
| |
Collapse
|
16
|
Abstract
INTRODUCTION Phenylketonuria (PKU) is a disorder of protein metabolism resulting in an accumulation of phenylalanine in the body. Dietary management consists of altering the sources of ingested protein to limit phenylalanine intake. Current dietary protein guidelines for PKU are based on limited scientific evidence, thus it remains unclear whether current practice leads to optimal protein status in people with PKU. To date, no attempt has been made to systematically evaluate the protein status of people with PKU, using a combination of validated anthropometric, biochemical and functional measurement tools. Furthermore, factors known to influence protein status in the general population warrant consideration when determining protein status in individuals with PKU, alongside factors unique to PKU such as the type of protein substitute consumed. Understanding the impact of these variables on protein status is crucial to developing a personalised approach to protein recommendations for optimising health and functional outcomes in people with PKU. Therefore, the aim of this scoping review is to examine existing evidence regarding the protein status of people with PKU, and to investigate the nutritional and lifestyle variables that influence protein status. METHODS AND ANALYSIS This review will be guided by Arksey and O'Malley's framework, along with guidance from Levac et al, Pawliuk et al and the Joanna Briggs Institute. The following databases will be searched: MEDLINE (Ovid), Embase, CENTRAL, Web of Science and Scopus, alongside grey literature. Identified literature will be assessed by two independent reviewers for inclusion. Descriptive numerical analysis will be performed and a narrative summary will accompany the tabulated results describing how study findings relate to the review questions. ETHICS AND DISSEMINATION This review protocol does not require ethical approval. Findings will be disseminated through peer-reviewed publication, presented at relevant conferences, and shared with a patient research advisory group to inform discussions on future research.
Collapse
Affiliation(s)
- Sarah Firman
- Department of Nutritional Sciences, King's College London, London, UK
- Adult Inherited Metabolic Diseases, Guy's and St Thomas' NHS Foundation Trust, London, UK
| | - Radha Ramachandran
- Adult Inherited Metabolic Diseases, Guy's and St Thomas' NHS Foundation Trust, London, UK
| | - Kevin Whelan
- Department of Nutritional Sciences, King's College London, London, UK
| | - Oliver C Witard
- Department of Nutritional Sciences, King's College London, London, UK
- Centre for Human and Applied Physiological Sciences, King's College London, London, UK
| | - Majella O'Keeffe
- Department of Nutritional Sciences, King's College London, London, UK
- School of Food and Nutritional Sciences, University College Cork, Cork, Ireland
| |
Collapse
|
17
|
Willis CRG, Gallagher IJ, Wilkinson DJ, Brook MS, Bass JJ, Phillips BE, Smith K, Etheridge T, Stokes T, McGlory C, Gorissen SHM, Szewczyk NJ, Phillips SM, Atherton PJ. Transcriptomic links to muscle mass loss and declines in cumulative muscle protein synthesis during short-term disuse in healthy younger humans. FASEB J 2021; 35:e21830. [PMID: 34342902 DOI: 10.1096/fj.202100276rr] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2021] [Revised: 07/05/2021] [Accepted: 07/19/2021] [Indexed: 12/13/2022]
Abstract
Muscle disuse leads to a rapid decline in muscle mass, with reduced muscle protein synthesis (MPS) considered the primary physiological mechanism. Here, we employed a systems biology approach to uncover molecular networks and key molecular candidates that quantitatively link to the degree of muscle atrophy and/or extent of decline in MPS during short-term disuse in humans. After consuming a bolus dose of deuterium oxide (D2 O; 3 mL.kg-1 ), eight healthy males (22 ± 2 years) underwent 4 days of unilateral lower-limb immobilization. Bilateral muscle biopsies were obtained post-intervention for RNA sequencing and D2 O-derived measurement of MPS, with thigh lean mass quantified using dual-energy X-ray absorptiometry. Application of weighted gene co-expression network analysis identified 15 distinct gene clusters ("modules") with an expression profile regulated by disuse and/or quantitatively connected to disuse-induced muscle mass or MPS changes. Module scans for candidate targets established an experimentally tractable set of candidate regulatory molecules (242 hub genes, 31 transcriptional regulators) associated with disuse-induced maladaptation, many themselves potently tied to disuse-induced reductions in muscle mass and/or MPS and, therefore, strong physiologically relevant candidates. Notably, we implicate a putative role for muscle protein breakdown-related molecular networks in impairing MPS during short-term disuse, and further establish DEPTOR (a potent mTOR inhibitor) as a critical mechanistic candidate of disuse driven MPS suppression in humans. Overall, these findings offer a strong benchmark for accelerating mechanistic understanding of short-term muscle disuse atrophy that may help expedite development of therapeutic interventions.
Collapse
Affiliation(s)
- Craig R G Willis
- Department of Sport and Health Sciences, College of Life and Environmental Sciences, University of Exeter, Exeter, UK
| | - Iain J Gallagher
- Faculty of Health Sciences and Sport, University of Stirling, Stirling, UK
| | - Daniel J Wilkinson
- MRC-Versus Arthritis Centre for Musculoskeletal Ageing Research and National Institute of Health Research, Nottingham Biomedical Research Centre, Royal Derby Hospital Centre, School of Medicine, University of Nottingham, Derby, UK
| | - Matthew S Brook
- MRC-Versus Arthritis Centre for Musculoskeletal Ageing Research and National Institute of Health Research, Nottingham Biomedical Research Centre, Royal Derby Hospital Centre, School of Medicine, University of Nottingham, Derby, UK
| | - Joseph J Bass
- MRC-Versus Arthritis Centre for Musculoskeletal Ageing Research and National Institute of Health Research, Nottingham Biomedical Research Centre, Royal Derby Hospital Centre, School of Medicine, University of Nottingham, Derby, UK
| | - Bethan E Phillips
- MRC-Versus Arthritis Centre for Musculoskeletal Ageing Research and National Institute of Health Research, Nottingham Biomedical Research Centre, Royal Derby Hospital Centre, School of Medicine, University of Nottingham, Derby, UK
| | - Kenneth Smith
- MRC-Versus Arthritis Centre for Musculoskeletal Ageing Research and National Institute of Health Research, Nottingham Biomedical Research Centre, Royal Derby Hospital Centre, School of Medicine, University of Nottingham, Derby, UK
| | - Timothy Etheridge
- Department of Sport and Health Sciences, College of Life and Environmental Sciences, University of Exeter, Exeter, UK
| | - Tanner Stokes
- Department of Kinesiology, McMaster University, Hamilton, ON, Canada
| | - Chris McGlory
- Department of Kinesiology, McMaster University, Hamilton, ON, Canada
| | | | - Nathaniel J Szewczyk
- MRC-Versus Arthritis Centre for Musculoskeletal Ageing Research and National Institute of Health Research, Nottingham Biomedical Research Centre, Royal Derby Hospital Centre, School of Medicine, University of Nottingham, Derby, UK.,Ohio Musculoskeletal and Neurological Institute (OMNI) and Department of Biomedical Sciences, Ohio University, Athens, OH, USA
| | - Stuart M Phillips
- Department of Kinesiology, McMaster University, Hamilton, ON, Canada
| | - Philip J Atherton
- MRC-Versus Arthritis Centre for Musculoskeletal Ageing Research and National Institute of Health Research, Nottingham Biomedical Research Centre, Royal Derby Hospital Centre, School of Medicine, University of Nottingham, Derby, UK
| |
Collapse
|
18
|
Choi SJ, Lee MS, Kang DH, Ko GJ, Lim HS, Yu BC, Park MY, Kim JK, Kim CH, Hwang SD, Kim JC, Won CW, An WS. Myostatin/Appendicular Skeletal Muscle Mass (ASM) Ratio, Not Myostatin, Is Associated with Low Handgrip Strength in Community-Dwelling Older Women. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2021; 18:ijerph18147344. [PMID: 34299795 PMCID: PMC8307565 DOI: 10.3390/ijerph18147344] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/11/2021] [Revised: 07/04/2021] [Accepted: 07/06/2021] [Indexed: 01/08/2023]
Abstract
Background/Aims: Elevated levels of serum myostatin have been proposed as a biomarker for sarcopenia. Recent studies have shown that elevated level of serum myostatin was associated with physical fitness and performance. This study aimed to examine the significance of myostatin in the association between muscle mass and physical performance in the elderly. Methods: This cross-sectional study is based on the Korean Frailty and Aging Cohort study involving 1053 people aged 70 years or over. Anthropometric, physical performance, and laboratory data were collected. Results: The mean age of the participants was 75.8 years, and 50.7% of them were female. Serum myostatin levels in men (3.7 ± 1.2 vs. 3.2 ± 1.1 ng/mL, p < 0.001) were higher compared with that in women. Serum myostatin level was associated with appendicular skeletal muscle mass (ASM) index and eGFR by cystatin C. Serum myostatin/ASM ratio was associated with handgrip strength in women. Conclusion: Higher serum myostatin levels were related with higher muscle mass and better physical performances in the elderly. Serum myostatin/ASM ratio may be a predictor for physical performance rather than myostatin.
Collapse
Affiliation(s)
- Soo Jeong Choi
- Division of Nephrology, Department of Internal Medicine, Soonchunhyang University College of Medicine, Bucheon 14584, Korea; (S.J.C.); (B.C.Y.); (M.Y.P.); (J.K.K.); (S.D.H.)
| | - Min Sung Lee
- Division of Nephrology, Department of Internal Medicine, Ewha Womans University College of Medicine, Seoul 07804, Korea; (M.S.L.); (D.-H.K.)
| | - Duk-Hee Kang
- Division of Nephrology, Department of Internal Medicine, Ewha Womans University College of Medicine, Seoul 07804, Korea; (M.S.L.); (D.-H.K.)
| | - Gang Jee Ko
- Division of Nephrology, Department of Internal Medicine, Korea University College of Medicine, Seoul 08308, Korea;
| | - Hee-Sook Lim
- Department of Food Sciences and Nutrition, Yeonsung University, Anyang 14011, Korea;
| | - Byung Chul Yu
- Division of Nephrology, Department of Internal Medicine, Soonchunhyang University College of Medicine, Bucheon 14584, Korea; (S.J.C.); (B.C.Y.); (M.Y.P.); (J.K.K.); (S.D.H.)
| | - Moo Yong Park
- Division of Nephrology, Department of Internal Medicine, Soonchunhyang University College of Medicine, Bucheon 14584, Korea; (S.J.C.); (B.C.Y.); (M.Y.P.); (J.K.K.); (S.D.H.)
| | - Jin Kuk Kim
- Division of Nephrology, Department of Internal Medicine, Soonchunhyang University College of Medicine, Bucheon 14584, Korea; (S.J.C.); (B.C.Y.); (M.Y.P.); (J.K.K.); (S.D.H.)
| | - Chul-Hee Kim
- Division of Endocrinology and Metabolism, Department of Internal Medicine, Soonchunhyang University College of Medicine, Bucheon 14854, Korea;
| | - Seung Duk Hwang
- Division of Nephrology, Department of Internal Medicine, Soonchunhyang University College of Medicine, Bucheon 14584, Korea; (S.J.C.); (B.C.Y.); (M.Y.P.); (J.K.K.); (S.D.H.)
| | - Jun Chul Kim
- Division of Nephrology, Department of Internal Medicine, CHA University School of Medicine, Gumi 39295, Korea;
| | - Chang Won Won
- Department of Family Medicine, Kyung Hee University School of Medicine, Seoul 02447, Korea
- Correspondence: (C.W.W.); (W.S.A.)
| | - Won Suk An
- Division of Nephrology, Department of Internal Medicine, Dong-A University College of Medicine, Busan 49201, Korea
- Correspondence: (C.W.W.); (W.S.A.)
| |
Collapse
|
19
|
Belova SP, Tyganov SA, Mochalova EP, Shenkman BS. Restricted Activity and Protein Synthesis
in Postural and Locomotor Muscles. J EVOL BIOCHEM PHYS+ 2021. [DOI: 10.1134/s0022093021030194] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
|
20
|
McKendry J, Stokes T, Mcleod JC, Phillips SM. Resistance Exercise, Aging, Disuse, and Muscle Protein Metabolism. Compr Physiol 2021; 11:2249-2278. [PMID: 34190341 DOI: 10.1002/cphy.c200029] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Skeletal muscle is the organ of locomotion, its optimal function is critical for athletic performance, and is also important for health due to its contribution to resting metabolic rate and as a site for glucose uptake and storage. Numerous endogenous and exogenous factors influence muscle mass. Much of what is currently known regarding muscle protein turnover is owed to the development and use of stable isotope tracers. Skeletal muscle mass is determined by the meal- and contraction-induced alterations of muscle protein synthesis and muscle protein breakdown. Increased loading as resistance training is the most potent nonpharmacological strategy by which skeletal muscle mass can be increased. Conversely, aging (sarcopenia) and muscle disuse lead to the development of anabolic resistance and contribute to the loss of skeletal muscle mass. Nascent omics-based technologies have significantly improved our understanding surrounding the regulation of skeletal muscle mass at the gene, transcript, and protein levels. Despite significant advances surrounding the mechanistic intricacies that underpin changes in skeletal muscle mass, these processes are complex, and more work is certainly needed. In this article, we provide an overview of the importance of skeletal muscle, describe the influence that resistance training, aging, and disuse exert on muscle protein turnover and the molecular regulatory processes that contribute to changes in muscle protein abundance. © 2021 American Physiological Society. Compr Physiol 11:2249-2278, 2021.
Collapse
Affiliation(s)
- James McKendry
- Exercise Metabolism Research Group, Department of Kinesiology, McMaster University, Hamilton, Ontario, Canada
| | - Tanner Stokes
- Exercise Metabolism Research Group, Department of Kinesiology, McMaster University, Hamilton, Ontario, Canada
| | - Jonathan C Mcleod
- Exercise Metabolism Research Group, Department of Kinesiology, McMaster University, Hamilton, Ontario, Canada
| | - Stuart M Phillips
- Exercise Metabolism Research Group, Department of Kinesiology, McMaster University, Hamilton, Ontario, Canada
| |
Collapse
|
21
|
Paulussen KJM, McKenna CF, Beals JW, Wilund KR, Salvador AF, Burd NA. Anabolic Resistance of Muscle Protein Turnover Comes in Various Shapes and Sizes. Front Nutr 2021; 8:615849. [PMID: 34026802 PMCID: PMC8131552 DOI: 10.3389/fnut.2021.615849] [Citation(s) in RCA: 40] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2020] [Accepted: 03/01/2021] [Indexed: 12/18/2022] Open
Abstract
Anabolic resistance is defined by a blunted stimulation of muscle protein synthesis rates (MPS) to common anabolic stimuli in skeletal muscle tissue such as dietary protein and exercise. Generally, MPS is the target of most exercise and feeding interventions as muscle protein breakdown rates seem to be less responsive to these stimuli. Ultimately, the blunted responsiveness of MPS to dietary protein and exercise underpins the loss of the amount and quality of skeletal muscle mass leading to decrements in physical performance in these populations. The increase of both habitual physical activity (including structured exercise that targets general fitness characteristics) and protein dense food ingestion are frontline strategies utilized to support muscle mass, performance, and health. In this paper, we discuss anabolic resistance as a common denominator underpinning muscle mass loss with aging, obesity, and other disease states. Namely, we discuss the fact that anabolic resistance exists as a dimmer switch, capable of varying from higher to lower levels of resistance, to the main anabolic stimuli of feeding and exercise depending on the population. Moreover, we review the evidence on whether increased physical activity and targeted exercise can be leveraged to restore the sensitivity of skeletal muscle tissue to dietary amino acids regardless of the population.
Collapse
Affiliation(s)
- Kevin J. M. Paulussen
- Department of Kinesiology and Community Health, University of Illinois at Urbana-Champaign, Urbana, IL, United States
| | - Colleen F. McKenna
- Division of Nutritional Sciences, University of Illinois at Urbana-Champaign, Urbana, IL, United States
| | - Joseph W. Beals
- Center for Human Nutrition, Washington University School of Medicine, St. Louis, MO, United States
| | - Kenneth R. Wilund
- Department of Kinesiology and Community Health, University of Illinois at Urbana-Champaign, Urbana, IL, United States
- Division of Nutritional Sciences, University of Illinois at Urbana-Champaign, Urbana, IL, United States
| | - Amadeo F. Salvador
- Department of Kinesiology and Community Health, University of Illinois at Urbana-Champaign, Urbana, IL, United States
| | - Nicholas A. Burd
- Department of Kinesiology and Community Health, University of Illinois at Urbana-Champaign, Urbana, IL, United States
- Division of Nutritional Sciences, University of Illinois at Urbana-Champaign, Urbana, IL, United States
| |
Collapse
|
22
|
Balboa-Castillo T, Andrade-Mayorga O, Marzuca-Nassr GN, Morales Illanes G, Ortiz M, Schiferlli I, Aguilar-Farias N, Soto Á, Sapunar J. Pre-existing conditions in Latin America and factors associated with adverse outcomes of COVID-19: A review. Medwave 2021; 21:e8181. [PMID: 34037583 DOI: 10.5867/medwave.2021.04.8180] [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: 09/23/2020] [Accepted: 03/02/2021] [Indexed: 11/27/2022] Open
Abstract
The coronavirus disease 2019 (COVID-19) pandemic, produced by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has spread rapidly throughout the world. Latin American and the Caribbean countries have been harshly affected by the pandemic mainly due to less prepared healthcare systems and fragmented social safety nets. In the region, health status population-based indicators are worse than compared to the Organization for Economic Cooperation and Development. Recent evidence suggests that the progression and severity of COVID-19 are associated with the prior health status of individuals, and studies have shown that the case fatality rate is highly stratified among different populations. This narrative review aims to describe factors associated with adverse outcomes of COVID-19 in the context of social determinants of health in Latin American and Caribbean countries. In this review, we state that genetic and biological factors interact in a sophisticated way with social determinants of health, impacting the rapid spread of COVID-19 in Latin American and Caribbean countries. Behavioral factors, such as physical inactivity, smoking, and unhealthy diets, are related to chronic systemic inflammation. Also, air pollution can prolong inflammation and the hyper-activation of the immune system. Air pollutants could facilitate the spread of the virus. Finally, frailty and comorbidities can be associated with COVID-19 severity through increasing vulnerability to stressors and leading to more severe symptoms of COVID-19 disease, including a higher mortality risk. All these factors contribute to increasing the impact of COVID-19 in Latin American and Caribbean countries. We highlight the relevance of considering social determinants of health in Latin American and the Caribbean countries, not only in controlling the likelihood of getting the disease but also its progression and severity. All these social determinants can guide the design and implementation of tailored interventions promoting healthy lifestyle behaviors, which should lower the spread of the disease, its severity, and lethality.
Collapse
Affiliation(s)
- Teresa Balboa-Castillo
- Centro de Investigación en Epidemiología Cardiometabólica y Nutricional (EPICYN); Faculty of Medicine, Universidad de La Frontera, Temuco, Chile. . Address: Avenida Alemania 458, Temuco, Chile. Postal code: 4810296. ORCID: 0000-0002-8568-7539
| | - Omar Andrade-Mayorga
- Centro de Investigación en Epidemiología Cardiometabólica y Nutricional (EPICYN), Faculty of Medicine, Universidad de La Frontera, Temuco, Chile; Department of Preclinical Sciences, Faculty of Medicine, Universidad de La Frontera, Temuco, Chile. ORCID: 0000-0003-3359-4100
| | - Gabriel Nasri Marzuca-Nassr
- Centro de Investigación en Epidemiología Cardiometabólica y Nutricional (EPICYN), Faculty of Medicine, Universidad de La Frontera, Temuco, Chile; Department of Internal Medicine, Faculty of Medicine, Universidad de La Frontera, Temuco, Chile. ORCID: 0000-0002-4835-7821
| | - Gladys Morales Illanes
- Centro de Investigación en Epidemiología Cardiometabólica y Nutricional (EPICYN), Faculty of Medicine, Universidad de La Frontera, Temuco, Chile; Public Health Department, Faculty of Medicine, Universidad de La Frontera, Temuco, Chile. ORCID: 0000-0001-7194-8833
| | - Manuel Ortiz
- Centro de Investigación en Epidemiología Cardiometabólica y Nutricional (EPICYN), Faculty of Medicine, Universidad de La Frontera, Temuco, Chile; Department of Psychology, Universidad de La Frontera, Temuco, Chile. ORCID: 0000-0002-7749-0699
| | - Ingrid Schiferlli
- Centro de Investigación en Epidemiología Cardiometabólica y Nutricional (EPICYN), Faculty of Medicine, Universidad de La Frontera, Temuco, Chile; Public Health Department, Faculty of Medicine, Universidad de La Frontera, Temuco, Chile. ORCID: 0000-0002-1309-4339
| | - Nicolas Aguilar-Farias
- Centro de Investigación en Epidemiología Cardiometabólica y Nutricional (EPICYN), Faculty of Medicine, Universidad de La Frontera, Temuco, Chile; Department of Physical Education, Sports and Recreation, Universidad de La Frontera, Temuco, Chile. ORCID: 0000-0002-6974-1312
| | - Álvaro Soto
- Centro de Investigación en Epidemiología Cardiometabólica y Nutricional (EPICYN), Faculty of Medicine, Universidad de La Frontera, Temuco, Chile; Department of Medical Specialties, Faculty of Medicine, Universidad de La Frontera, Temuco, Chile. ORCID: 0000-0003-2583-7854
| | - Jorge Sapunar
- Centro de Investigación en Epidemiología Cardiometabólica y Nutricional (EPICYN), Faculty of Medicine, Universidad de La Frontera, Temuco, Chile; Department of Internal Medicine, Faculty of Medicine, Universidad de La Frontera, Temuco, Chile. ORCID: 0000-0001-9908-8054
| |
Collapse
|
23
|
Daily Myofibrillar Protein Synthesis Rates in Response to Low- and High-Frequency Resistance Exercise Training in Healthy, Young Men. Int J Sport Nutr Exerc Metab 2021; 31:209-216. [PMID: 33601335 DOI: 10.1123/ijsnem.2020-0274] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2020] [Revised: 11/21/2020] [Accepted: 11/21/2020] [Indexed: 11/18/2022]
Abstract
The impact of resistance exercise frequency on muscle protein synthesis rates remains unknown. The aim of this study was to compare daily myofibrillar protein synthesis rates over a 7-day period of low-frequency (LF) versus high-frequency (HF) resistance exercise training. Nine young men (21 ± 2 years) completed a 7-day period of habitual physical activity (BASAL). This was followed by a 7-day exercise period of volume-matched, LF (10 × 10 repetitions at 70% one-repetition maximum, once per week) or HF (2 × 10 repetitions at ∼70% one-repetition maximum, five times per week) resistance exercise training. The participants had one leg randomly allocated to LF and the other to HF. Skeletal muscle biopsies and daily saliva samples were collected to determine myofibrillar protein synthesis rates using 2H2O, with intracellular signaling determined using Western blotting. The myofibrillar protein synthesis rates did not differ between the LF (1.46 ± 0.26%/day) and HF (1.48 ± 0.33%/day) conditions over the 7-day exercise training period (p > .05). There were no significant differences between the LF and HF conditions over the first 2 days (1.45 ± 0.41%/day vs. 1.25 ± 0.46%/day) or last 5 days (1.47 ± 0.30%/day vs. 1.50 ± 0.41%/day) of the exercise training period (p > .05). Daily myofibrillar protein synthesis rates were not different from BASAL at any time point during LF or HF (p > .05). The phosphorylation status and total protein content of selected proteins implicated in skeletal muscle ribosomal biogenesis were not different between conditions (p > .05). Under the conditions of the present study, resistance exercise training frequency did not modulate daily myofibrillar protein synthesis rates in young men.
Collapse
|
24
|
Abstract
INTRODUCTION Two benefits of acute exercise are the next day's lowering of the postprandial plasma triglyceride response to a high-fat meal and increased fat oxidation. However, if activity levels (daily steps) are very low, these acute adaptations to exercise do not occur. This phenomenon has been termed "exercise resistance." This study sought to systematically reduce daily step number and identify the range of step counts that elicit "exercise resistance." METHODS Ten participants completed three, 5-d trials in a randomized, crossover design with differing levels of step reduction. After 2 d of controlled activity, participants completed 2 d of LOW, LIMITED, or NORMAL steps (2675 ± 314, 4759 ± 276, and 8481 ± 581 steps per day, respectively). Participants completed a 1-h bout of running on the evening of the second day. High-fat tolerance tests were performed on the next morning, and postprandial responses were compared. RESULTS After LOW and LIMITED, postprandial incremental area under the curve (AUC) of plasma triglyceride was elevated 22%-23% compared with NORMAL (P < 0.05). Whole body fat oxidation was also significantly lower (16%-19%, P < 0.05, respectively) in LOW and LIMITED compared with NORMAL. No significant differences were found between LOW and LIMITED. CONCLUSION Two days of step reduction to approximately 2500-5000 steps per day in young healthy individuals impairs the ability of an acute bout of exercise to increase fat oxidation and attenuate postprandial increases in plasma triglycerides. This suggests that "exercise resistance" occurs in individuals taking approximately 5000 or fewer steps per day, whereas 8500 steps per day protects against exercise resistance in fat metabolism. It seems that fat metabolism is influenced more by the inhibitory effects of inactivity than by the stimulating effects derived from 1 h of moderate-intensity running.
Collapse
Affiliation(s)
- Heath M Burton
- Human Performance Laboratory, Department of Kinesiology and Health Education, University of Texas at Austin, Austin, TX
| | | |
Collapse
|
25
|
Smeuninx B, Elhassan YS, Manolopoulos KN, Sapey E, Rushton AB, Edwards SJ, Morgan PT, Philp A, Brook MS, Gharahdaghi N, Smith K, Atherton PJ, Breen L. The effect of short-term exercise prehabilitation on skeletal muscle protein synthesis and atrophy during bed rest in older men. J Cachexia Sarcopenia Muscle 2021; 12:52-69. [PMID: 33347733 PMCID: PMC7890266 DOI: 10.1002/jcsm.12661] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/09/2020] [Revised: 10/19/2020] [Accepted: 11/24/2020] [Indexed: 12/21/2022] Open
Abstract
BACKGROUND Poor recovery from periods of disuse accelerates age-related muscle loss, predisposing individuals to the development of secondary adverse health outcomes. Exercise prior to disuse (prehabilitation) may prevent muscle deterioration during subsequent unloading. The present study aimed to investigate the effect of short-term resistance exercise training (RET) prehabilitation on muscle morphology and regulatory mechanisms during 5 days of bed rest in older men. METHODS Ten healthy older men aged 65-80 years underwent four bouts of high-volume unilateral leg RET over 7 days prior to 5 days of inpatient bed rest. Physical activity and step-count were monitored over the course of RET prehabilitation and bed rest, whilst dietary intake was recorded throughout. Prior to and following bed rest, quadriceps cross-sectional area (CSA), and hormone/lipid profiles were determined. Serial muscle biopsies and dual-stable isotope tracers were used to determine integrated myofibrillar protein synthesis (iMyoPS) over RET prehabilitation and bed rest phases, and acute postabsorptive and postprandial myofibrillar protein synthesis (aMyoPS) rates at the end of bed rest. RESULTS During bed rest, daily step-count and light and moderate physical activity time decreased, whilst sedentary time increased when compared with habitual levels (P < 0.001 for all). Dietary protein and fibre intake during bed rest were lower than habitual values (P < 0.01 for both). iMyoPS rates were significantly greater in the exercised leg (EX) compared with the non-exercised control leg (CTL) over prehabilitation (1.76 ± 0.37%/day vs. 1.36 ± 0.18%/day, respectively; P = 0.007). iMyoPS rates decreased similarly in EX and CTL during bed rest (CTL, 1.07 ± 0.22%/day; EX, 1.30 ± 0.38%/day; P = 0.037 and 0.002, respectively). Postprandial aMyoPS rates increased above postabsorptive values in EX only (P = 0.018), with no difference in delta postprandial aMyoPS stimulation between legs. Quadriceps CSA at 40%, 60%, and 80% of muscle length decreased significantly in EX and CTL over bed rest (0.69%, 3.5%, and 2.8%, respectively; P < 0.01 for all), with no differences between legs. No differences in fibre-type CSA were observed between legs or with bed rest. Plasma insulin and serum lipids did not change with bed rest. CONCLUSIONS Short-term resistance exercise prehabilitation augmented iMyoPS rates in older men but did not offset the relative decline in iMyoPS and muscle mass during bed rest.
Collapse
Affiliation(s)
- Benoit Smeuninx
- School of Sport, Exercise and Rehabilitation SciencesUniversity of BirminghamBirminghamUK
| | - Yasir S. Elhassan
- Institute of Metabolism and Systems ResearchUniversity of BirminghamBirminghamUK
- Centre for Endocrinology, Diabetes and MetabolismBirmingham Health PartnersBirminghamUK
| | - Konstantinos N. Manolopoulos
- Institute of Metabolism and Systems ResearchUniversity of BirminghamBirminghamUK
- Centre for Endocrinology, Diabetes and MetabolismBirmingham Health PartnersBirminghamUK
| | - Elizabeth Sapey
- NIHR Clinical Research Facility, University Hospitals Birmingham NHS Foundation Trust and Institute of Inflammation and AgeingUniversity of BirminghamBirminghamUK
| | - Alison B. Rushton
- School of Sport, Exercise and Rehabilitation SciencesUniversity of BirminghamBirminghamUK
| | - Sophie J. Edwards
- School of Sport, Exercise and Rehabilitation SciencesUniversity of BirminghamBirminghamUK
| | - Paul T. Morgan
- School of Sport, Exercise and Rehabilitation SciencesUniversity of BirminghamBirminghamUK
| | - Andrew Philp
- Garvan Institute of Medical ResearchSydneyNSWAustralia
- St Vincents Medical School, UNSW MedicineUNSW SydneySydneyNSWAustralia
| | - Matthew S. Brook
- MRC‐ARUK Centre of Excellence for Musculoskeletal Ageing Research, Clinical, Metabolic and Molecular PhysiologyUniversity of NottinghamDerbyUK
| | - Nima Gharahdaghi
- MRC‐ARUK Centre of Excellence for Musculoskeletal Ageing Research, Clinical, Metabolic and Molecular PhysiologyUniversity of NottinghamDerbyUK
| | - Kenneth Smith
- MRC‐ARUK Centre of Excellence for Musculoskeletal Ageing Research, Clinical, Metabolic and Molecular PhysiologyUniversity of NottinghamDerbyUK
| | - Philip J. Atherton
- MRC‐ARUK Centre of Excellence for Musculoskeletal Ageing Research, Clinical, Metabolic and Molecular PhysiologyUniversity of NottinghamDerbyUK
| | - Leigh Breen
- School of Sport, Exercise and Rehabilitation SciencesUniversity of BirminghamBirminghamUK
- MRC‐Arthritis Research UK Centre for Musculoskeletal Ageing ResearchUniversity of BirminghamUK
| |
Collapse
|
26
|
Hendriks FK, Kooman JP, van Loon LJ. Dietary protein interventions to improve nutritional status in end-stage renal disease patients undergoing hemodialysis. Curr Opin Clin Nutr Metab Care 2021; 24:79-87. [PMID: 33060457 PMCID: PMC7752218 DOI: 10.1097/mco.0000000000000703] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
PURPOSE OF REVIEW Poor nutritional status is prevalent among end-stage renal disease patients undergoing hemodialysis. Chronic hemodialysis patients show an accelerated decline in skeletal muscle mass and strength, which is associated with higher mortality rates and a reduced quality of life. The current review aims to summarize recent advances regarding underlying causes of muscle loss and interventions that support muscle mass maintenance in patients with chronic hemodialysis. RECENT FINDINGS Muscle maintenance in chronic hemodialysis patients is compromised by low dietary protein intake levels, anabolic resistance of skeletal muscle tissue, sedentary behavior, and amino acid removal during hemodialysis. Studies assessing the effect of increased protein intake on nutritional status generally show beneficial results, especially in hypoalbuminemic chronic hemodialysis patients. The muscle protein synthetic response following protein ingestion in chronic hemodialysis patients may be enhanced through incorporation of structured physical activity and/or concurrent ketoacid ingestion. SUMMARY A coordinated program that combines nutritional and physical activity interventions is likely required to attenuate the decline in muscle mass and strength of chronic hemodialysis patients. Nephrologists, dieticians, and exercise specialists should collaborate closely to establish guidelines regarding the appropriate quantity and timing of protein ingestion. In addition, they should provide tailored nutritional and physical activity interventions for chronic hemodialysis patients (see video, Supplemental Digital Content 1, Video abstract, http://links.lww.com/COCN/A14).
Collapse
Affiliation(s)
- Floris K. Hendriks
- Department of Human Biology
- Department of Internal Medicine, NUTRIM School of Nutrition and Translational Research in Metabolism
| | - Jeroen P. Kooman
- Department of Internal Medicine, NUTRIM School of Nutrition and Translational Research in Metabolism
- Division of Nephrology, Department of Internal Medicine, Maastricht University Medical Centre+, Maastricht, The Netherlands
| | | |
Collapse
|
27
|
Dietary protein, exercise, ageing and physical inactivity: interactive influences on skeletal muscle proteostasis. Proc Nutr Soc 2020; 80:106-117. [PMID: 33023679 DOI: 10.1017/s0029665120007879] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Dietary protein is a pre-requisite for the maintenance of skeletal muscle mass; stimulating increases in muscle protein synthesis (MPS), via essential amino acids (EAA), and attenuating muscle protein breakdown, via insulin. Muscles are receptive to the anabolic effects of dietary protein, and in particular the EAA leucine, for only a short period (i.e. about 2-3 h) in the rested state. Thereafter, MPS exhibits tachyphylaxis despite continued EAA availability and sustained mechanistic target of rapamycin complex 1 signalling. Other notable characteristics of this 'muscle full' phenomenon include: (i) it cannot be overcome by proximal intake of additional nutrient signals/substrates regulating MPS; meaning a refractory period exists before a next stimulation is possible, (ii) it is refractory to pharmacological/nutraceutical enhancement of muscle blood flow and thus is not induced by muscle hypo-perfusion, (iii) it manifests independently of whether protein intake occurs in a bolus or intermittent feeding pattern, and (iv) it does not appear to be dependent on protein dose per se. Instead, the main factor associated with altering muscle full is physical activity. For instance, when coupled to protein intake, resistance exercise delays the muscle full set-point to permit additional use of available EAA for MPS to promote muscle remodelling/growth. In contrast, ageing is associated with blunted MPS responses to protein/exercise (anabolic resistance), while physical inactivity (e.g. immobilisation) induces a premature muscle full, promoting muscle atrophy. It is crucial that in catabolic scenarios, anabolic strategies are sought to mitigate muscle decline. This review highlights regulatory protein turnover interactions by dietary protein, exercise, ageing and physical inactivity.
Collapse
|
28
|
Myostatin as a Biomarker of Muscle Wasting and other Pathologies-State of the Art and Knowledge Gaps. Nutrients 2020; 12:nu12082401. [PMID: 32796600 PMCID: PMC7469036 DOI: 10.3390/nu12082401] [Citation(s) in RCA: 60] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2020] [Revised: 08/06/2020] [Accepted: 08/08/2020] [Indexed: 12/14/2022] Open
Abstract
Sarcopenia is a geriatric syndrome with a significant impact on older patients’ quality of life, morbidity and mortality. Despite the new available criteria, its early diagnosis remains difficult, highlighting the necessity of looking for a valid muscle wasting biomarker. Myostatin, a muscle mass negative regulator, is one of the potential candidates. The aim of this work is to point out various factors affecting the potential of myostatin as a biomarker of muscle wasting. Based on the literature review, we can say that recent studies produced conflicting results and revealed a number of potential confounding factors influencing their use in sarcopenia diagnosing. These factors include physiological variables (such as age, sex and physical activity) as well as a variety of disorders (including heart failure, metabolic syndrome, kidney failure and inflammatory diseases) and differences in laboratory measurement methodology. Our conclusion is that although myostatin alone might not prove to be a feasible biomarker, it could become an important part of a recently proposed panel of muscle wasting biomarkers. However, a thorough understanding of the interrelationship of these markers, as well as establishing a valid measurement methodology for myostatin and revising current research data in the light of new criteria of sarcopenia, is needed.
Collapse
|
29
|
Abstract
The ongoing global pandemic brought on by the spread of the novel coronavirus SARS-CoV-2 is having profound effects on human health and well-being. With no viable vaccine presently available and the virus being rapidly transmitted, governments and national health authorities have acted swiftly, recommending 'lockdown' policies and/or various levels of social restriction/isolation to attenuate the rate of infection. An immediate consequence of these strategies is reduced exposure to daylight, which can result in marked changes in patterns of daily living such as the timing of meals, and sleep. These disruptions to circadian biology have severe cardiometabolic health consequences for susceptible individuals. We discuss the consequences of reductions in patterns of daily physical activity and the resulting energy imbalance induced by periods of isolation, along with several home-based strategies to maintain cardiometabolic health in the forthcoming months.
Collapse
|
30
|
McKendry J, Thomas ACQ, Phillips SM. Muscle Mass Loss in the Older Critically Ill Population: Potential Therapeutic Strategies. Nutr Clin Pract 2020; 35:607-616. [PMID: 32578900 DOI: 10.1002/ncp.10540] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2020] [Revised: 04/29/2020] [Accepted: 05/16/2020] [Indexed: 12/14/2022] Open
Abstract
Skeletal muscle plays a critical role in everyday life, and its age-associated reduction has severe health consequences. The pre-existing presence of sarcopenia, combined with anabolic resistance, protein undernutrition, and the pro-catabolic/anti-anabolic milieu induced by aging and exacerbated in critical care, may accelerate the rate at which skeletal muscle is lost in patients with critical illness. Advancements in intensive care unit (ICU)-care provision have drastically improved survival rates; therefore, attention can be redirected toward other significant issues affecting ICU patients (e.g., length of stay, days on ventilation, nosocomial disease development, etc.). Thus, strategies targeting muscle mass and function losses within an ICU setting are essential to improve patient-related outcomes. Notably, loading exercise and protein provision are the most compelling. Many older ICU patients seldom meet the recommended protein intake, and loading exercise is difficult to conduct in the ICU. Nevertheless, the incorporation of physical therapy (PT), neuromuscular electrical stimulation, and early mobilization strategies may be beneficial. Furthermore, a number of nutrition practices within the ICU have been shown to improve patient-related outcomes ((e.g., feeding strategy [i.e., oral, early enteral, or parenteral]), be hypocaloric (∼70%-80% energy requirements), and increase protein provision (∼1.2-2.5 g/kg/d)). The aim of this brief review is to discuss the dysregulation of muscle mass maintenance in an older ICU population and highlight the potential benefits of strategic nutrition practice, specifically protein, and PT within the ICU. Finally, we provide some general guidelines that may serve to counteract muscle mass loss in patients with critical illness.
Collapse
Affiliation(s)
- James McKendry
- Exercise Metabolism Research Group, Department of Kinesiology, McMaster University, Hamilton, Ontario, Canada
| | - Aaron C Q Thomas
- Exercise Metabolism Research Group, Department of Kinesiology, McMaster University, Hamilton, Ontario, Canada
| | - Stuart M Phillips
- Exercise Metabolism Research Group, Department of Kinesiology, McMaster University, Hamilton, Ontario, Canada
| |
Collapse
|
31
|
Marshall RN, Smeuninx B, Morgan PT, Breen L. Nutritional Strategies to Offset Disuse-Induced Skeletal Muscle Atrophy and Anabolic Resistance in Older Adults: From Whole-Foods to Isolated Ingredients. Nutrients 2020; 12:nu12051533. [PMID: 32466126 PMCID: PMC7284346 DOI: 10.3390/nu12051533] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2020] [Revised: 05/19/2020] [Accepted: 05/22/2020] [Indexed: 12/14/2022] Open
Abstract
Preserving skeletal muscle mass and functional capacity is essential for healthy ageing. Transient periods of disuse and/or inactivity in combination with sub-optimal dietary intake have been shown to accelerate the age-related loss of muscle mass and strength, predisposing to disability and metabolic disease. Mechanisms underlying disuse and/or inactivity-related muscle deterioration in the older adults, whilst multifaceted, ultimately manifest in an imbalance between rates of muscle protein synthesis and breakdown, resulting in net muscle loss. To date, the most potent intervention to mitigate disuse-induced muscle deterioration is mechanical loading in the form of resistance exercise. However, the feasibility of older individuals performing resistance exercise during disuse and inactivity has been questioned, particularly as illness and injury may affect adherence and safety, as well as accessibility to appropriate equipment and physical therapists. Therefore, optimising nutritional intake during disuse events, through the introduction of protein-rich whole-foods, isolated proteins and nutrient compounds with purported pro-anabolic and anti-catabolic properties could offset impairments in muscle protein turnover and, ultimately, the degree of muscle atrophy and recovery upon re-ambulation. The current review therefore aims to provide an overview of nutritional countermeasures to disuse atrophy and anabolic resistance in older individuals.
Collapse
Affiliation(s)
- Ryan N. Marshall
- School of Sport, Exercise and Rehabilitation Sciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK; (R.N.M.); (B.S.); (P.T.M.)
- Medical Research Council-Versus Arthritis Centre for Musculoskeletal Ageing, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK
| | - Benoit Smeuninx
- School of Sport, Exercise and Rehabilitation Sciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK; (R.N.M.); (B.S.); (P.T.M.)
- Medical Research Council-Versus Arthritis Centre for Musculoskeletal Ageing, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK
- Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, VIC 3052, Australia
| | - Paul T. Morgan
- School of Sport, Exercise and Rehabilitation Sciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK; (R.N.M.); (B.S.); (P.T.M.)
- Medical Research Council-Versus Arthritis Centre for Musculoskeletal Ageing, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK
| | - Leigh Breen
- School of Sport, Exercise and Rehabilitation Sciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK; (R.N.M.); (B.S.); (P.T.M.)
- Medical Research Council-Versus Arthritis Centre for Musculoskeletal Ageing, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK
- Correspondence: ; Tel.: +44-121-414-4109
| |
Collapse
|
32
|
Jakobsson J, Malm C, Furberg M, Ekelund U, Svensson M. Physical Activity During the Coronavirus (COVID-19) Pandemic: Prevention of a Decline in Metabolic and Immunological Functions. Front Sports Act Living 2020; 2:57. [PMID: 33345048 PMCID: PMC7739799 DOI: 10.3389/fspor.2020.00057] [Citation(s) in RCA: 71] [Impact Index Per Article: 17.8] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2020] [Accepted: 04/21/2020] [Indexed: 12/19/2022] Open
Affiliation(s)
- Johan Jakobsson
- Section of Sports Medicine, Department of Community Medicine and Rehabilitation, Umeå University, Umeå, Sweden
| | - Christer Malm
- Section of Sports Medicine, Department of Community Medicine and Rehabilitation, Umeå University, Umeå, Sweden
| | - Maria Furberg
- Department of Clinical Microbiology, Umeå University, Umeå, Sweden
| | - Ulf Ekelund
- Department of Sports Medicine, Norwegian School of Sport Sciences, Oslo, Norway.,Norwegian Institute of Public Health, Oslo, Norway
| | - Michael Svensson
- Section of Sports Medicine, Department of Community Medicine and Rehabilitation, Umeå University, Umeå, Sweden
| |
Collapse
|
33
|
Kilroe SP, Fulford J, Holwerda AM, Jackman SR, Lee BP, Gijsen AP, van Loon LJC, Wall BT. Short-term muscle disuse induces a rapid and sustained decline in daily myofibrillar protein synthesis rates. Am J Physiol Endocrinol Metab 2020; 318:E117-E130. [PMID: 31743039 DOI: 10.1152/ajpendo.00360.2019] [Citation(s) in RCA: 51] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Short-term muscle disuse has been reported to lower both postabsorptive and postprandial myofibrillar protein synthesis rates. This study assessed the impact of disuse on daily myofibrillar protein synthesis rates following short-term (2 and 7 days) muscle disuse under free living conditions. Thirteen healthy young men (age: 20 ± 1 yr; BMI: 23 ± 1 kg/m-2) underwent 7 days of unilateral leg immobilization via a knee brace, with the nonimmobilized leg acting as a control. Four days before immobilization participants ingested 400 mL of 70% deuterated water, with 50-mL doses consumed daily thereafter. Upper leg bilateral MRI scans and muscle biopsies were collected before and after 2 and 7 days of immobilization to determine quadriceps volume and daily myofibrillar protein synthesis rates. Immobilization reduced quadriceps volume in the immobilized leg by 1.7 ± 0.3 and 6.7 ± 0.6% after 2 and 7 days, respectively, with no changes in the control leg. Over the 1-wk immobilization period, myofibrillar protein synthesis rates were 36 ± 4% lower in the immobilized (0.81 ± 0.04%/day) compared with the control (1.26 ± 0.04%/day) leg (P < 0.001). Myofibrillar protein synthesis rates in the control leg did not change over time (P = 0.775), but in the immobilized leg they were numerically lower during the 0- to 2-day period (16 ± 6%, 1.11 ± 0.09%/day, P = 0.153) and were significantly lower during the 2- to 7-day period (44 ± 5%, 0.70 ± 0.06%/day, P < 0.001) when compared with the control leg. We conclude that 1 wk of muscle disuse induces a rapid and sustained decline in daily myofibrillar protein synthesis rates in healthy young men.
Collapse
Affiliation(s)
- Sean P Kilroe
- Department of Sport and Health Sciences, College of Life and Environmental Science, University of Exeter, Exeter, United Kingdom
| | - Jonathan Fulford
- Peninsula National Institute for Health Research Clinical Research Facility, College of Medicine and Health, University of Exeter, Exeter, United Kingdom
| | - Andrew M Holwerda
- Department of Human Biology, NUTRIM School of Nutrition and Translational Research in Metabolism, Maastricht University Medical Centre, Maastricht, The Netherlands
| | - Sarah R Jackman
- Department of Sport and Health Sciences, College of Life and Environmental Science, University of Exeter, Exeter, United Kingdom
| | - Benjamin P Lee
- Institute of Biomedical and Clinical Science, University of Exeter Medical School, Exeter, Devon, United Kingdom
| | - Annemie P Gijsen
- Department of Human Biology, NUTRIM School of Nutrition and Translational Research in Metabolism, Maastricht University Medical Centre, Maastricht, The Netherlands
| | - Luc J C van Loon
- Department of Human Biology, NUTRIM School of Nutrition and Translational Research in Metabolism, Maastricht University Medical Centre, Maastricht, The Netherlands
| | - Benjamin T Wall
- Department of Sport and Health Sciences, College of Life and Environmental Science, University of Exeter, Exeter, United Kingdom
| |
Collapse
|
34
|
Kim K, Reid BA, Casey CA, Bender BE, Ro B, Song Q, Trewin AJ, Petersen AC, Kuang S, Gavin TP, Roseguini BT. Effects of repeated local heat therapy on skeletal muscle structure and function in humans. J Appl Physiol (1985) 2020; 128:483-492. [PMID: 31971474 DOI: 10.1152/japplphysiol.00701.2019] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
The purpose of the present study was to examine the effects of repeated exposure to local heat therapy (HT) on skeletal muscle function, myofiber morphology, capillarization, and mitochondrial content in humans. Twelve young adults (23.6 ± 4.8 yr, body mass index 24.9 ± 3.0 kg/m2) had one randomly selected thigh treated with HT (garment perfused with water at ~52°C) for 8 consecutive weeks (90 min, 5 days/wk) while the opposite thigh served as a control. Biopsies were obtained from the vastus lateralis muscle before and after 4 and 8 wk of treatment. Knee extensor strength and fatigue resistance were also assessed using isokinetic dynamometry. The changes in peak isokinetic torque were higher (P = 0.007) in the thigh exposed to HT than in the control thigh at weeks 4 (control 4.2 ± 13.1 Nm vs. HT 9.1 ± 16.1 Nm) and 8 (control 1.8 ± 9.7 Nm vs. HT 7.8 ± 10.2 Nm). Exposure to HT averted a temporal decline in capillarization around type II fibers (P < 0.05), but had no effect on capillarization indexes in type I fibers. The content of endothelial nitric oxide synthase was ~18% and 35% higher in the thigh exposed to HT at 4 and 8 wk, respectively (P = 0.003). Similarly, HT increased the content of small heat shock proteins HSPB5 (P = 0.007) and HSPB1 (P = 0.009). There were no differences between thighs for the changes in fiber cross-sectional area and mitochondrial content. These results indicate that exposure to local HT for 8 wk promotes a proangiogenic environment and enhances muscle strength but does not affect mitochondrial content in humans.NEW & NOTEWORTHY We demonstrate that repeated application of heat therapy to the thigh with a garment perfused with warm water enhances the strength of knee extensors and influences muscle capillarization in parallel with increases in the content of endothelial nitric oxide synthase and small heat shock proteins. This practical method of passive heat stress may be a feasible tool to treat conditions associated with capillary rarefaction and muscle weakness.
Collapse
Affiliation(s)
- Kyoungrae Kim
- Department of Health and Kinesiology, Purdue University, West Lafayette, Indiana
| | - Blake A Reid
- Department of Health and Kinesiology, Purdue University, West Lafayette, Indiana
| | - Caitlin A Casey
- Department of Health and Kinesiology, Purdue University, West Lafayette, Indiana
| | - Brooke E Bender
- Department of Health and Kinesiology, Purdue University, West Lafayette, Indiana
| | - Bohyun Ro
- Department of Health and Kinesiology, Purdue University, West Lafayette, Indiana
| | - Qifan Song
- Department of Statistics, Purdue University, West Lafayette, Indiana
| | - Adam J Trewin
- Institute for Health and Sport, Victoria University, Melbourne, Victoria, Australia
| | - Aaron C Petersen
- Institute for Health and Sport, Victoria University, Melbourne, Victoria, Australia
| | - Shihuan Kuang
- Department of Animal Sciences, Purdue University, West Lafayette, Indiana
| | - Timothy P Gavin
- Department of Health and Kinesiology, Purdue University, West Lafayette, Indiana
| | - Bruno T Roseguini
- Department of Health and Kinesiology, Purdue University, West Lafayette, Indiana
| |
Collapse
|
35
|
Hendriks FK, Smeets JSJ, van der Sande FM, Kooman JP, van Loon LJC. Dietary Protein and Physical Activity Interventions to Support Muscle Maintenance in End-Stage Renal Disease Patients on Hemodialysis. Nutrients 2019; 11:E2972. [PMID: 31817402 PMCID: PMC6950262 DOI: 10.3390/nu11122972] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2019] [Revised: 12/01/2019] [Accepted: 12/03/2019] [Indexed: 01/10/2023] Open
Abstract
End-stage renal disease patients have insufficient renal clearance capacity left to adequately excrete metabolic waste products. Hemodialysis (HD) is often employed to partially replace renal clearance in these patients. However, skeletal muscle mass and strength start to decline at an accelerated rate after initiation of chronic HD therapy. An essential anabolic stimulus to allow muscle maintenance is dietary protein ingestion. Chronic HD patients generally fail to achieve recommended protein intake levels, in particular on dialysis days. Besides a low protein intake on dialysis days, the protein equivalent of a meal is extracted from the circulation during HD. Apart from protein ingestion, physical activity is essential to allow muscle maintenance. Unfortunately, most chronic HD patients have a sedentary lifestyle. Yet, physical activity and nutritional interventions to support muscle maintenance are generally not implemented in routine patient care. To support muscle maintenance in chronic HD patients, quantity and timing of protein intake should be optimized, in particular throughout dialysis days. Furthermore, implementing physical activity either during or between HD sessions may improve the muscle protein synthetic response to protein ingestion. A well-orchestrated combination of physical activity and nutritional interventions will be instrumental to preserve muscle mass in chronic HD patients.
Collapse
Affiliation(s)
- Floris K. Hendriks
- Department of Human Biology, NUTRIM School of Nutrition and Translational Research in Metabolism, Maastricht University Medical Centre+, P.O. Box 616, 6200 MD Maastricht, The Netherlands; (F.K.H.)
- Department of Internal Medicine, NUTRIM School of Nutrition and Translational Research in Metabolism, Maastricht University Medical Centre+, P.O. Box 616, 6200 MD Maastricht, The Netherlands;
| | - Joey S. J. Smeets
- Department of Human Biology, NUTRIM School of Nutrition and Translational Research in Metabolism, Maastricht University Medical Centre+, P.O. Box 616, 6200 MD Maastricht, The Netherlands; (F.K.H.)
| | - Frank M. van der Sande
- Division of Nephrology, Department of Internal Medicine, Maastricht University Medical Centre+, P.O. Box 5800, 6202 AZ Maastricht, The Netherlands
| | - Jeroen P. Kooman
- Department of Internal Medicine, NUTRIM School of Nutrition and Translational Research in Metabolism, Maastricht University Medical Centre+, P.O. Box 616, 6200 MD Maastricht, The Netherlands;
- Division of Nephrology, Department of Internal Medicine, Maastricht University Medical Centre+, P.O. Box 5800, 6202 AZ Maastricht, The Netherlands
| | - Luc J. C. van Loon
- Department of Human Biology, NUTRIM School of Nutrition and Translational Research in Metabolism, Maastricht University Medical Centre+, P.O. Box 616, 6200 MD Maastricht, The Netherlands; (F.K.H.)
| |
Collapse
|