ArticlePloS one2019
Extraordinary fast-twitch fiber abundance in elite weightlifters.
Article in PloS one, 2019. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 26 papers, 2 of them syntheses that pooled it.
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Who cites it
26 citing papers in PubMed, 2 syntheses or guidelines pooled it.
- Sex differences in human skeletal muscle fiber types and the influence of age, physical activity, and muscle group: A systematic review and meta-analysis.Physiological reports · 2025Pooled it
- Pooled it
- The X genotype of the ACTN3 sports gene is associated with the endurance of the sportsperson from the South Indian population: a short study.European journal of applied physiology · 2026Article
- Maximal eccentric-concentric strength determines stretch-shortening cycle leg power across biological sexes.Scientific reports · 2026Article
- Influence of foot arch height on isokinetic knee muscle strength at varying angular velocities.Frontiers in sports and active living · 2026Article
- GWAS-based polygenic profiling across broad sport categories: shared and category-specific genetic associations with athlete status and polygenic differences from population controls.Frontiers in sports and active living · 2026Article
- Fast Myosin Binding Protein-C Is a Vital Regulator in Young and Aged Fast Skeletal Muscle Homeostasis.Journal of cachexia, sarcopenia and muscle · 2025Article
- Review
- Evolution of resistance training in women: History and mechanisms for health and performance.Sports medicine and health science · 2025Review
- Crosstalk Between Skeletal Muscle and Proximal Connective Tissues in Lipid Dysregulation in Obesity and Type 2 Diabetes.Metabolites · 2025Review
- Sprinters' and Marathon Runners' Performances Are Better Explained by Muscle Fibers' Percentage Cross-Sectional Area than Any Other Parameter of Muscle Fiber Composition.Sports (Basel, Switzerland) · 2025Article
- Neuromuscular adaptations to resistance training in elite versus recreational athletes.Frontiers in physiology · 2025Review
- TheMetabolites · 2024Article
- Optimizing Resistance Training for Sprint and Endurance Athletes: Balancing Positive and Negative Adaptations.Sports medicine (Auckland, N.Z.) · 2024Review
- Sports-Related Genomic Predictors Are Associated with Athlete Status in Chinese Sprint/Power Athletes.Genes · 2024Article
- Muscle fiber phenotype: a culprit of abnormal metabolism and function in skeletal muscle of humans with obesity.American journal of physiology. Endocrinology and metabolism · 2023Review
- The molecular athlete: exercise physiology from mechanisms to medals.Physiological reviews · 2023Review
- Localized Heat Therapy Improves Mitochondrial Respiratory Capacity but Not Fatty Acid Oxidation.International journal of molecular sciences · 2022Article
- Possibility for Visualizing the Muscle Microstructure by q-Space Imaging Technique.Applied bionics and biomechanics · 2022Article
- Muscle Fiber Type Transitions with Exercise Training: Shifting Perspectives.Sports (Basel, Switzerland) · 2021Review
Corrections and comments
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Authors and funding
8 authors.
Funding
No grant is acknowledged in the PubMed record.
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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