ArticleJournal of cachexia, sarcopenia and muscle2019
Hybrid fiber alterations in exercising seniors suggest contribution to fast-to-slow muscle fiber shift.
Article in Journal of cachexia, sarcopenia and muscle, 2019. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 20 papers.
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20 citing papers in PubMed, 32 citations in OpenAlex.
- Traditional Chinese Medicine for Diabetic Sarcopenia: A Review and Its Related Mechanisms.Journal of diabetes research · 2026Review
- Optimizing the methodology for precise estimation of skeletal muscle fiber type proportions in humans.Scientific reports · 2025Article
- Fiber-type composition and 3D capillary analysis of the human splenius capitis muscle.Biomolecules & biomedicine · 2025Article
- Molecular composition of skeletal muscle in infants and adults: a comparative proteomic and transcriptomic study.Scientific reports · 2024Article
- Endurance exercise-induced histone methylation modification involved in skeletal muscle fiber type transition and mitochondrial biogenesis.Scientific reports · 2024Article
- Type 2 diabetes mellitus related sarcopenia: a type of muscle loss distinct from sarcopenia and disuse muscle atrophy.Frontiers in endocrinology · 2024Review
- Reprogramming of cis-regulatory networks during skeletal muscle atrophy in male mice.Nature communications · 2023Article
- Faecal microbiota transplantation from young rats attenuates age-related sarcopenia revealed by multiomics analysis.Journal of cachexia, sarcopenia and muscle · 2023Article
- FTO-dependent mClinical epigenetics · 2023Article
- Decrements of mobility and power in recreationally active septuagenarians is related to loss of force, but not slowing of the muscle: a 5-year longitudinal study.European journal of applied physiology · 2023Article
- Using the articularis genu to test peri-articular muscle health during knee osteoarthritis.Scientific reports · 2022Article
- MOTS-c increases in skeletal muscle following long-term physical activity and improves acute exercise performance after a single dose.Physiological reports · 2022Article
- Tent5a modulates muscle fiber formation in adolescent idiopathic scoliosis via maintenance of myogenin expression.Cell proliferation · 2022Article
- Exercise-mediated reinnervation of skeletal muscle in elderly people: An update.European journal of translational myology · 2022Article
- Injection of Micronized Human Amnion/Chorion Membrane Results in Increased Early Supraspinatus Muscle Regeneration in a Chronic Model of Rotator Cuff Tear.Annals of biomedical engineering · 2021Article
- Heterogeneity of the strength response to progressive resistance exercise training in older adults: Contributions of muscle contractility.Experimental gerontology · 2021Article
- Semiautomatic morphometric analysis of skeletal muscle obtained by needle biopsy in older adults.GeroScience · 2020Article
- Role of Menopausal Transition and Physical Activity in Loss of Lean and Muscle Mass: A Follow-Up Study in Middle-Aged Finnish Women.Journal of clinical medicine · 2020Article
- Age-specific differences in the time-frequency representation of surface electromyographic data recorded during a submaximal cyclic back extension exercise: a promising biomarker to detect early signs of sarcopenia.Journal of neuroengineering and rehabilitation · 2020Article
- Hybrid fiber alterations in exercising seniors suggest contribution to fast-to-slow muscle fiber shift.Journal of cachexia, sarcopenia and muscle · 2019Article
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Authors and funding
7 authors at 1 institution in 1 country.
Funding
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Abstract
backgroundHuman skeletal muscle is composed of a functional and metabolic continuum of slow (Type I) and fast fibers (IIa and IIx). Hybrid fibers co-expressing different myosin heavy chains are also present and seem to be more prominent in aging muscle. Their role is debated; hybrid fibers were reported either in a transitional state, between slow and fast fibers, or as fixed individual entities. This study examined the fate of hybrid fibers with an endurance exercise intervention in an elderly sedentary population.
methodsTwenty-two sedentary healthy elderly men and women underwent a 16-week supervised endurance exercise intervention. Eighteen endurance-trained age- and gender-matched volunteers served as controls. Fiber type distribution was determined by immunohistochemistry on vastus lateralis muscle biopsies pre-intervention and post-intervention.
resultsA total of 13840 fibers were analyzed. At baseline, a Type II dominant fiber profile was observed compared with the control group, with more Type IIa (P = 0.0301) and Type IIx fibers (P = 0.0328). Hybrid fibers represented almost 5% of total muscle fibers in both groups. There was no significant difference between groups (I-IIa, P = 0.6719 and IIa-IIx, P = 0.0998). Intervention triggered qualitative dynamics towards an increase in Type I, and decrease in Type II fibers, paralleled by an increase in I-IIa hybrids (P = 0.0301).
conclusionsThe present study is, to our knowledge, the first to examine hybrid muscle fiber type adaptations to an endurance exercise intervention in the elderly. Hybrid fiber proportions did not differ between chronic sedentary state and chronic endurance-trained state. Exercise intervention increased Type I-IIa hybrid fibers along with shift dynamics in other fiber types suggesting the contribution of hybrid fiber to a fast-to-slow fiber type transition, eventually serving as intermediate reservoir from one monomorphic myosin heavy chain expressing fiber type to another. This finding favours the transitional theory regarding hybrid muscle fibers and exercise, crucial to understanding reversible mechanisms of sarcopenia and development of prevention measures.
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