ArticleJournal of applied physiology (Bethesda, Md. : 1985)2014
Age-related structural alterations in human skeletal muscle fibers and mitochondria are sex specific: relationship to single-fiber function.
Article in Journal of applied physiology (Bethesda, Md. : 1985), 2014. The graph could read no effect estimate from its abstract, so it casts no vote on the map. It is linked to trial NCT01190046 (Muscle Disuse and Contractile Dysfunction in the Elderly), which is not on this map. Cited by 55 papers, 2 of them syntheses that pooled it.
What it found
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The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
The trial behind it
Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
Muscle Disuse and Contractile Dysfunction in the Elderly
Who cites it
55 citing papers in PubMed, 2 syntheses or guidelines pooled it.
- Effects of age on human skeletal muscle: a systematic review and meta-analysis of myosin heavy chain isoform protein expression, fiber size, and distribution.American journal of physiology. Cell physiology · 2024Pooled it
- Exercise training upregulates intracellular nicotinamide phosphoribosyltransferase expression in humans: a systematic review with meta-analysis.Frontiers in public health · 2023Pooled it
- Sustaining neuromuscular activation after total knee arthroplasty preserves skeletal muscle fiber size, contractility, and innervation in older adults.Experimental gerontology · 2025Trial
- Utility of Neuromuscular Electrical Stimulation to Preserve Quadriceps Muscle Fiber Size and Contractility After Anterior Cruciate Ligament Injuries and Reconstruction: A Randomized, Sham-Controlled, Blinded Trial.The American journal of sports medicine · 2020Trial
- Effect of neuromuscular electrical stimulation on skeletal muscle size and function in patients with breast cancer receiving chemotherapy.Journal of applied physiology (Bethesda, Md. : 1985) · 2020Trial
- Resistance training-induced gains in knee extensor strength are related to increased neural cell adhesion molecule expression in older adults with knee osteoarthritis.BMC research notes · 2019Trial
- Myopathy in endogenous Cushing's syndrome: type II muscle fiber atrophy and its association with age and circulating IGF-1.Endocrine connections · 2026Article
- Ageing-related structural and cellular alterations in the mouse muscle-tendon junction.Biogerontology · 2026Article
- Time to Reset: The Interplay Between Circadian Rhythms and Redox Homeostasis in Skeletal Muscle Ageing and Systemic Health.Antioxidants (Basel, Switzerland) · 2025Review
- Responses of skeletal muscle to mechanical stimuli in female rats following and during muscle disuse atrophy.Journal of applied physiology (Bethesda, Md. : 1985) · 2025Article
- Article
- Understanding Secondary Sarcopenia Development in Young Adults Using Pig Model with Chronic Pancreatitis.International journal of molecular sciences · 2024Article
- Mitochondrial Quality Control Processes at the Crossroads of Cell Death and Survival: Mechanisms and Signaling Pathways.International journal of molecular sciences · 2024Review
- Impact of capillary and sarcolemmal proximity on mitochondrial structure and energetic function in skeletal muscle.The Journal of physiology · 2024Article
- Article
- Skeletal muscle adaptations in patients with lung cancer: Longitudinal observations from the whole body to cellular level.Journal of cachexia, sarcopenia and muscle · 2023Article
- Preoperative Lower-Limb Muscle Predictors for Gait Speed Improvement after Total Hip Arthroplasty for Patients with Osteoarthritis.Journal of personalized medicine · 2023Article
- Curcumin as a Therapeutic Agent for Sarcopenia.Nutrients · 2023Review
- Sex Differences in Inflammation and Muscle Wasting in Aging and Disease.International journal of molecular sciences · 2023Review
- The myonuclear domain in adult skeletal muscle fibres: past, present and future.The Journal of physiology · 2023Review
Corrections and comments
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Authors and funding
7 authors.
Funding
Abstract
Age-related loss of skeletal muscle mass and function is implicated in the development of disease and physical disability. However, little is known about how age affects skeletal muscle structure at the cellular and ultrastructural levels or how such alterations impact function. Thus we examined skeletal muscle structure at the tissue, cellular, and myofibrillar levels in young (21-35 yr) and older (65-75 yr) male and female volunteers, matched for habitual physical activity level. Older adults had smaller whole muscle tissue cross-sectional areas (CSAs) and mass. At the cellular level, older adults had reduced CSAs in myosin heavy chain II (MHC II) fibers, with no differences in MHC I fibers. In MHC II fibers, older men tended to have fewer fibers with large CSAs, while older women showed reduced fiber size across the CSA range. Older adults showed a decrease in intermyofibrillar mitochondrial size; however, the age effect was driven primarily by women (i.e., age by sex interaction effect). Mitochondrial size was inversely and directly related to isometric tension and myosin-actin cross-bridge kinetics, respectively. Notably, there were no intermyofibrillar or subsarcolemmal mitochondrial fractional content or myofilament ultrastructural differences in the activity-matched young and older adults. Collectively, our results indicate age-related reductions in whole muscle size do not vary by sex. However, age-related structural alterations at the cellular and subcellular levels are different between the sexes and may contribute to different functional phenotypes in ways that modulate sex-specific reductions in physical capacity with age.
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Registered trials
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