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Moesgaard L, Jessen S, Mackey AL, Hostrup M. Myonuclear addition is associated with sex-specific fiber hypertrophy and occurs in relation to fiber perimeter not cross-sectional area. J Appl Physiol (1985) 2022; 133:732-741. [PMID: 35952346 DOI: 10.1152/japplphysiol.00235.2022] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
It is unclear whether resistance training-induced myofiber hypertrophy is affected by sex, and whether myonuclear addition occurs in relation to the myonuclear domain and can contribute to explaining a potential sex-specific hypertrophic response. This study investigated the effect of 8 weeks of resistance training on myofiber hypertrophy and myonuclear addition in 12 males (28±7 years; mean±SD) and 12 females (27±7 years). Muscle biopsies were collected from m. vastus lateralis before and after the training intervention and analyzed by immunohistochemistry for fiber type and size, satellite cells, and myonuclei. Hypertrophy of type I fibers was greater in males than females (P<0.05), whereas hypertrophy of type II fibers was similar between sexes (P=0.158‒0.419). Expansion of the satellite cell pool (P=0.132‒0.667) and myonuclear addition (P=0.064‒0.228) did not differ significantly between sexes, irrespective of myofiber type. However, when individual responses to resistance training were assessed, myonuclear addition was strongly correlated with fiber hypertrophy (r=0.68‒0.85, P<0.001). While myofiber hypertrophy was accompanied by an increase in myonuclear domain (P<0.05), fiber perimeter per myonucleus remained constant throughout the study (P=0.096‒0.666). These findings indicate that myonuclear addition occurs in relation to the fiber perimeter per myonucleus, not the myonuclear domain, and has a substantial role in muscle hypertrophy, but does not fully explain greater hypertrophy of type I fibers in males than females.
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Affiliation(s)
- Lukas Moesgaard
- The August Krogh Section for Human Physiology, Department of Nutrition, Exercise and Sports, University of Copenhagen, Copenhagen, Denmark
| | - Søren Jessen
- The August Krogh Section for Human Physiology, Department of Nutrition, Exercise and Sports, University of Copenhagen, Copenhagen, Denmark
| | - Abigail L Mackey
- Institute of Sports Medicine Copenhagen, Department of Orthopedic Surgery, Copenhagen University Hospital - Bispebjerg and Frederiksberg, and Department of Clinical Medicine, University of Copenhagen, Copenhagen, Denmark.,Xlab, Center for Healthy Aging, Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Morten Hostrup
- The August Krogh Section for Human Physiology, Department of Nutrition, Exercise and Sports, University of Copenhagen, Copenhagen, Denmark
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Lanza G, Pino M, Fisicaro F, Vagli C, Cantone M, Pennisi M, Bella R, Bellomo M. Motor activity and Becker's muscular dystrophy: lights and shadows. PHYSICIAN SPORTSMED 2020; 48:151-160. [PMID: 31646922 DOI: 10.1080/00913847.2019.1684810] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Becker's disease is an inherited muscular dystrophy caused by mutations in the gene coding for the dystrophin protein that leads to quantitative and/or qualitative protein dysfunction and consequent muscle degeneration. Studies in animal models demonstrate that, while eccentric or high-intensity training are deleterious for dystrophic muscles, low-intensity aerobic training may slowdown the disease process and progression. Based on these preclinical data, the available studies in patients with Becker's muscular dystrophy undergoing workout on a cycle ergometer or on a treadmill, at a heart rate ≤65% of their maximal oxygen uptake, showed that aerobic exercise counteracts physical deterioration and loss of functional abilities. These findings suggest an improvement of physical performance through an increase of muscle strength, fatigue resistance, and dexterity capacities, without substantial evidence of acceleration of muscular damage progression. Therefore, individually tailored mild-to-moderate intensity aerobic exercise should be considered as part of the management of these patients. However, further research is necessary to define specific and standardized guidelines for the prescription of type, intensity, frequency, and duration of motor activities. In this review, we provided a summary of the impact of physical activity both in animal models and in patients with Becker's muscular dystrophy, with the intent to identify trends and gaps in knowledge. The potential therapeutic implications and future research directions have been also highlighted.
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Affiliation(s)
- Giuseppe Lanza
- Department of Surgery and Medical-Surgical Specialties, University of Catania, Catania, Italy
- Department of Neurology IC, Oasi Research Institute - IRCCS, Troina, Italy
| | - Marcello Pino
- School of Human and Social Science, University Kore of Enna, Enna, Italy
| | - Francesco Fisicaro
- Department of Medical and Surgical Sciences and Advanced Technologies, University of Catania, Catania, Italy
| | - Carla Vagli
- Department of Medical and Surgical Sciences and Advanced Technologies, University of Catania, Catania, Italy
| | - Mariagiovanna Cantone
- Department of Neurology, Sant'Elia Hospital, ASP Caltanissetta, Caltanissetta, Italy
| | - Manuela Pennisi
- Department of Biomedical and Biotechnological Sciences, University of Catania, Catania, Italy
| | - Rita Bella
- Department of Medical and Surgical Sciences and Advanced Technologies, University of Catania, Catania, Italy
| | - Maria Bellomo
- School of Human and Social Science, University Kore of Enna, Enna, Italy
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Filipovic A, DeMarees M, Grau M, Hollinger A, Seeger B, Schiffer T, Bloch W, Gehlert S. Superimposed Whole-Body Electrostimulation Augments Strength Adaptations and Type II Myofiber Growth in Soccer Players During a Competitive Season. Front Physiol 2019; 10:1187. [PMID: 31607944 PMCID: PMC6768094 DOI: 10.3389/fphys.2019.01187] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2019] [Accepted: 09/02/2019] [Indexed: 12/25/2022] Open
Abstract
Background The improvement of strength and athletic performance during a competitive season in elite soccer players is a demanding task for the coach. Aims As whole-body electrostimulation (WB-EMS) training provides a time efficient stimulation potentially capable in exerting skeletal muscle adaptations we aimed to test this approach over 7 weeks in trained male soccer players during a competitive season. Hypothesis We hypothesized that a superimposed WB-EMS will increase maximal strength and type I and type II myofiber hypertrophy. Methods Twenty-eight male field soccer players were assigned in either a WB-EMS group (EG, n = 10), a training group (TG, n = 10), or a control group (CG, n = 8). The regular soccer training consists of two to four sessions and one match per week. In concurrent, the EG performed 3 × 10 squat jumps superimposed with WB-EMS twice per week, TG performed 3 × 10 squat jumps without EMS twice per week, and the CG only performed the regular soccer training. Muscle biopsies were collected and strength tests were performed under resting conditions before (Baseline) and after the intervention period (Posttest). Muscle biopsies were analyzed via western blotting and immunohistochemistry for skeletal muscle adaptive responses. To determine the effect of the training interventions a 2 × 3 (time ∗ group) mixed ANOVA with repeated measures was conducted. Results Maximal strength in leg press (p = 0.009) and leg curl (p = 0.026) was significantly increased in EG along with a small but significant increase in type II myofiber diameter (p = 0.023). All of these adaptations were not observed in TG and CG. Conclusion WB-EMS can serve as a time efficient training method to augment strength capacities and type II fiber myofiber growth in soccer players when combined with specific resistance training. This combination may therefore be a promising training modification compared to traditional strength training for performance enhancement.
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Affiliation(s)
- Andre Filipovic
- Section of Molecular and Cellular Sport Medicine, Institute of Cardiology and Sports Medicine, German Sport University Cologne, Cologne, Germany
| | - Markus DeMarees
- Section of Sports Medicine and Sports Nutrition, Faculty of Sports Science, Ruhr-University Bochum, Bochum, Germany
| | - Marijke Grau
- Section of Molecular and Cellular Sport Medicine, Institute of Cardiology and Sports Medicine, German Sport University Cologne, Cologne, Germany
| | - Anna Hollinger
- Section of Molecular and Cellular Sport Medicine, Institute of Cardiology and Sports Medicine, German Sport University Cologne, Cologne, Germany
| | - Benedikt Seeger
- Section of Molecular and Cellular Sport Medicine, Institute of Cardiology and Sports Medicine, German Sport University Cologne, Cologne, Germany
| | - Thorsten Schiffer
- Outpatient Clinic for Sports Traumatology and Public Health Consultation, German Sport University Cologne, Cologne, Germany
| | - Wilhelm Bloch
- Section of Molecular and Cellular Sport Medicine, Institute of Cardiology and Sports Medicine, German Sport University Cologne, Cologne, Germany
| | - Sebastian Gehlert
- Section of Molecular and Cellular Sport Medicine, Institute of Cardiology and Sports Medicine, German Sport University Cologne, Cologne, Germany.,Institute of Sport Science, Biosciences of Sports, University of Hildesheim, Hildesheim, Germany
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Extraordinary fast-twitch fiber abundance in elite weightlifters. PLoS One 2019; 14:e0207975. [PMID: 30917128 PMCID: PMC6436686 DOI: 10.1371/journal.pone.0207975] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2018] [Accepted: 02/15/2019] [Indexed: 11/19/2022] Open
Abstract
Human skeletal muscle fibers exist across a continuum of slow → fast-twitch. The amount of each fiber type (FT) influences muscle performance but remains largely unexplored in elite athletes, particularly from strength/power sports. To address this nescience, vastus lateralis (VL) biopsies were performed on World/Olympic (female, n = 6, "WCF") and National-caliber (female, n = 9, "NCF"; and male, n = 6, "NCM") American weightlifters. Participant accolades included 3 Olympic Games, 19 World Championships, 25 National records, and >170 National/International medals. Samples were analyzed for myosin heavy chain (MHC) content via SDS-PAGE using two distinct techniques: single fiber (SF) distribution (%) and homogenate (HG) composition. The main finding was that these athletes displayed the highest pure MHC IIa concentrations ever reported in healthy VL (23±9% I, 5±3% I/IIa, 67±13% IIa, and 6±10% IIa/IIx), with WCF expressing a notable 71±17% (NCF = 67±8%, NCM = 63±16%). No pure MHC IIx were found with SF. Secondary analysis revealed the heavyweights accounted for 91% of the MHC IIa/IIx fibers, which caused a correlation between this FT and body mass. Additionally, when compared to SF, HG overestimated MHC I (23±9 vs. 31±9%) and IIx (0±0 vs. 3±6%) by misclassifying I/IIa fibers as I and IIa/IIx fibers as IIx, highlighting the limitation of HG as a measure of isoform distribution. These results collectively suggest that athlete caliber (World vs. National) and/or years competing in the sport determine FT% more than sex, particularly for MHC IIa. The extreme fast-twitch myofiber abundance likely explains how elite weightlifters generate high forces in rapid time-frames.
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Heydemann A. Skeletal Muscle Metabolism in Duchenne and Becker Muscular Dystrophy-Implications for Therapies. Nutrients 2018; 10:nu10060796. [PMID: 29925809 PMCID: PMC6024668 DOI: 10.3390/nu10060796] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2018] [Revised: 06/14/2018] [Accepted: 06/16/2018] [Indexed: 02/06/2023] Open
Abstract
The interactions between nutrition and metabolism and skeletal muscle have long been known. Muscle is the major metabolic organ—it consumes more calories than other organs—and therefore, there is a clear need to discuss these interactions and provide some direction for future research areas regarding muscle pathologies. In addition, new experiments and manuscripts continually reveal additional highly intricate, reciprocal interactions between metabolism and muscle. These reciprocal interactions include exercise, age, sex, diet, and pathologies including atrophy, hypoxia, obesity, diabetes, and muscle myopathies. Central to this review are the metabolic changes that occur in the skeletal muscle cells of muscular dystrophy patients and mouse models. Many of these metabolic changes are pathogenic (inappropriate body mass changes, mitochondrial dysfunction, reduced adenosine triphosphate (ATP) levels, and increased Ca2+) and others are compensatory (increased phosphorylated AMP activated protein kinase (pAMPK), increased slow fiber numbers, and increased utrophin). Therefore, reversing or enhancing these changes with therapies will aid the patients. The multiple therapeutic targets to reverse or enhance the metabolic pathways will be discussed. Among the therapeutic targets are increasing pAMPK, utrophin, mitochondrial number and slow fiber characteristics, and inhibiting reactive oxygen species. Because new data reveals many additional intricate levels of interactions, new questions are rapidly arising. How does muscular dystrophy alter metabolism, and are the changes compensatory or pathogenic? How does metabolism affect muscular dystrophy? Of course, the most profound question is whether clinicians can therapeutically target nutrition and metabolism for muscular dystrophy patient benefit? Obtaining the answers to these questions will greatly aid patients with muscular dystrophy.
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Affiliation(s)
- Ahlke Heydemann
- Department of Physiology and Biophysics, University of Illinois at Chicago, Chicago, IL 60612, USA.
- Center for Cardiovascular Research, The University of Illinois at Chicago, Chicago, IL 60612, USA.
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AREVALO JOSEA, LYNN SCOTTK, BAGLEY JAMESR, BROWN LEEE, COSTA PABLOB, GALPIN ANDREWJ. Lower-Limb Dominance, Performance, and Fiber Type in Resistance-trained Men. Med Sci Sports Exerc 2018; 50:1054-1060. [DOI: 10.1249/mss.0000000000001533] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Murach KA, Fry CS, Kirby TJ, Jackson JR, Lee JD, White SH, Dupont-Versteegden EE, McCarthy JJ, Peterson CA. Starring or Supporting Role? Satellite Cells and Skeletal Muscle Fiber Size Regulation. Physiology (Bethesda) 2018; 33:26-38. [PMID: 29212890 PMCID: PMC5866409 DOI: 10.1152/physiol.00019.2017] [Citation(s) in RCA: 74] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2017] [Revised: 09/18/2017] [Accepted: 09/18/2017] [Indexed: 12/22/2022] Open
Abstract
Recent loss-of-function studies show that satellite cell depletion does not promote sarcopenia or unloading-induced atrophy, and does not prevent regrowth. Although overload-induced muscle fiber hypertrophy is normally associated with satellite cell-mediated myonuclear accretion, hypertrophic adaptation proceeds in the absence of satellite cells in fully grown adult mice, but not in young growing mice. Emerging evidence also indicates that satellite cells play an important role in remodeling the extracellular matrix during hypertrophy.
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Affiliation(s)
- Kevin A Murach
- The Center for Muscle Biology, University of Kentucky, Lexington, Kentucky
- Department of Rehabilitation Sciences, College of Health Sciences, University of Kentucky, Lexington, Kentucky
| | - Christopher S Fry
- Department of Nutrition and Metabolism, School of Health Professions, University of Texas Medical Branch at Galveston, Galveston, Texas
| | - Tyler J Kirby
- The Weill Institute for Cell and Molecular Biology, Cornell University, Ithaca, New York
| | - Janna R Jackson
- The Center for Muscle Biology, University of Kentucky, Lexington, Kentucky
- Department of Rehabilitation Sciences, College of Health Sciences, University of Kentucky, Lexington, Kentucky
| | - Jonah D Lee
- Environment, Health, and Safety, University of Michigan, Ann Arbor, Michigan
| | - Sarah H White
- Department of Animal Science, Texas A&M University, College Station, Texas; and
| | - Esther E Dupont-Versteegden
- The Center for Muscle Biology, University of Kentucky, Lexington, Kentucky
- Department of Rehabilitation Sciences, College of Health Sciences, University of Kentucky, Lexington, Kentucky
| | - John J McCarthy
- The Center for Muscle Biology, University of Kentucky, Lexington, Kentucky
- Department of Physiology, College of Medicine, University of Kentucky, Lexington, Kentucky
| | - Charlotte A Peterson
- The Center for Muscle Biology, University of Kentucky, Lexington, Kentucky;
- Department of Rehabilitation Sciences, College of Health Sciences, University of Kentucky, Lexington, Kentucky
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Murach KA, Confides AL, Ho A, Jackson JR, Ghazala LS, Peterson CA, Dupont-Versteegden EE. Depletion of Pax7+ satellite cells does not affect diaphragm adaptations to running in young or aged mice. J Physiol 2017; 595:6299-6311. [PMID: 28736900 DOI: 10.1113/jp274611] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2017] [Accepted: 07/18/2017] [Indexed: 12/14/2022] Open
Abstract
KEY POINTS Satellite cell depletion does not affect diaphragm adaptations to voluntary wheel running in young or aged mice. Satellite cell depletion early in life (4 months of age) has minimal effect on diaphragm phenotype by old age (24 months). Prolonged satellite cell depletion in the diaphragm does not result in excessive extracellular matrix accumulation, in contrast to what has been reported in hind limb muscles. Up-regulation of Pax3 mRNA+ cells after satellite cell depletion in young and aged mice suggests that Pax3+ cells may compensate for a loss of Pax7+ satellite cells in the diaphragm. Future investigations should focus on the role of Pax3+ cells in the diaphragm during adaptation to exercise and ageing. ABSTRACT Satellite cell contribution to unstressed diaphragm is higher compared to hind limb muscles, which is probably attributable to constant activation of this muscle to drive ventilation. Whether satellite cell depletion negatively impacts diaphragm quantitative and qualitative characteristics under stressed conditions in young and aged mice is unknown. We therefore challenged the diaphragm with prolonged running activity in the presence and absence of Pax7+ satellite cells in young and aged mice using an inducible Pax7CreER -R26RDTA model. Mice were vehicle (Veh, satellite cell-replete) or tamoxifen (Tam, satellite cell-depleted) treated at 4 months of age and were then allowed to run voluntarily at 6 months (young) and 22 months (aged). Age-matched, cage-dwelling, Veh- and Tam-treated mice without wheel access served as activity controls. Diaphragm muscles were analysed from young (8 months) and aged (24 months) mice. Satellite cell depletion did not alter diaphragm mean fibre cross-sectional area, fibre type distribution or extracellular matrix content in young or aged mice, regardless of running activity. Resting in vivo diaphragm function was also unaffected by satellite cell depletion. Myonuclear density was maintained in young satellite cell-depleted mice regardless of running, although it was modestly reduced in aged sedentary (-7%) and running (-19%) mice without satellite cells (P < 0.05). Using fluorescence in situ hybridization, we detected higher Pax3 mRNA+ cell density in both young and aged satellite cell-depleted diaphragm muscle (P < 0.05), which may compensate for the loss of Pax7+ satellite cells.
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Affiliation(s)
- Kevin A Murach
- College of Health Sciences, Department of Rehabilitation Sciences, and the Center for Muscle Biology, University of Kentucky, Lexington, KY, USA
| | - Amy L Confides
- College of Health Sciences, Department of Rehabilitation Sciences, and the Center for Muscle Biology, University of Kentucky, Lexington, KY, USA
| | - Angel Ho
- College of Health Sciences, Department of Rehabilitation Sciences, and the Center for Muscle Biology, University of Kentucky, Lexington, KY, USA
| | - Janna R Jackson
- College of Health Sciences, Department of Rehabilitation Sciences, and the Center for Muscle Biology, University of Kentucky, Lexington, KY, USA
| | - Lina S Ghazala
- College of Health Sciences, Department of Rehabilitation Sciences, and the Center for Muscle Biology, University of Kentucky, Lexington, KY, USA
| | - Charlotte A Peterson
- College of Health Sciences, Department of Rehabilitation Sciences, and the Center for Muscle Biology, University of Kentucky, Lexington, KY, USA
| | - Esther E Dupont-Versteegden
- College of Health Sciences, Department of Rehabilitation Sciences, and the Center for Muscle Biology, University of Kentucky, Lexington, KY, USA
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Murach KA, Walton RG, Fry CS, Michaelis SL, Groshong JS, Finlin BS, Kern PA, Peterson CA. Cycle training modulates satellite cell and transcriptional responses to a bout of resistance exercise. Physiol Rep 2016; 4:e12973. [PMID: 27650251 PMCID: PMC5037921 DOI: 10.14814/phy2.12973] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2016] [Accepted: 08/23/2016] [Indexed: 12/17/2022] Open
Abstract
This investigation evaluated whether moderate-intensity cycle ergometer training affects satellite cell and molecular responses to acute maximal concentric/eccentric resistance exercise in middle-aged women. Baseline and 72 h postresistance exercise vastus lateralis biopsies were obtained from seven healthy middle-aged women (56 ± 5 years, BMI 26 ± 1, VO2max 27 ± 4) before and after 12 weeks of cycle training. Myosin heavy chain (MyHC) I- and II-associated satellite cell density and cross-sectional area was determined via immunohistochemistry. Expression of 93 genes representative of the muscle-remodeling environment was also measured via NanoString. Overall fiber size increased ~20% with cycle training (P = 0.052). MyHC I satellite cell density increased 29% in response to acute resistance exercise before endurance training and 50% with endurance training (P < 0.05). Following endurance training, MyHC I satellite cell density decreased by 13% in response to acute resistance exercise (acute resistance × training interaction, P < 0.05). Genes with an interaction effect tracked with satellite cell behavior, increasing in the untrained state and decreasing in the endurance trained state in response to resistance exercise. Similar satellite cell and gene expression response patterns indicate coordinated regulation of the muscle environment to promote adaptation. Moderate-intensity endurance cycle training modulates the response to acute resistance exercise, potentially conditioning the muscle for more intense concentric/eccentric activity. These results suggest that cycle training is an effective endurance exercise modality for promoting growth in middle-aged women, who are susceptible to muscle mass loss with progressing age.
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Affiliation(s)
- Kevin A Murach
- Department of Rehabilitation Sciences, Center for Muscle Biology, College of Health Sciences, University of Kentucky, Lexington, Kentucky
| | - R Grace Walton
- Department of Rehabilitation Sciences, Center for Muscle Biology, College of Health Sciences, University of Kentucky, Lexington, Kentucky
| | - Christopher S Fry
- Department of Nutrition and Metabolism, University of Texas Medical Branch, Galveston, Texas
| | - Sami L Michaelis
- Department of Rehabilitation Sciences, Center for Muscle Biology, College of Health Sciences, University of Kentucky, Lexington, Kentucky
| | - Jason S Groshong
- Department of Rehabilitation Sciences, Center for Muscle Biology, College of Health Sciences, University of Kentucky, Lexington, Kentucky
| | - Brian S Finlin
- Division of Endocrinology, and Barnstable Brown Diabetes and Obesity Center, Department of Medicine, University of Kentucky, Lexington, Kentucky
| | - Philip A Kern
- Division of Endocrinology, and Barnstable Brown Diabetes and Obesity Center, Department of Medicine, University of Kentucky, Lexington, Kentucky
| | - Charlotte A Peterson
- Department of Rehabilitation Sciences, Center for Muscle Biology, College of Health Sciences, University of Kentucky, Lexington, Kentucky
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