REVIEW   

Minerva Ortopedica e Traumatologica 2018 September;69(3):90-4

DOI: 10.23736/S0394-3410.18.03886-9

Copyright © 2018 EDIZIONI MINERVA MEDICA

lingua: Inglese

Chronic muscle fatigue: the role of hormonal and stress factors

Teet SEENE ✉, Karin ALEV, Priit KAASIK

Institute of Sport Sciences and Physiotherapy, University of Tartu, Tartu, Estonia

The aim of this short review is to describe role of hormonal and stress factors in the development of muscle fatigue on the basis of glucocorticoid myopathy and exercise myopathy. Catabolic processes increased and anabolic decreased in skeletal muscle in both cases of myopathy. Intensive destruction of muscle fibers, myofibrils and degradation of contractile proteins are the main reasons for reduced muscle strength, motor activity, weakness and fatigue. Similarities and differences between developments of chronic muscle fatigue in both cases depend on oxidative capacity of muscle fibers. Fibers with low oxidative capacity are more sensitive to the action of glucocorticoids. Type I and IIA muscle fibers (higher oxidative capacity) are more susceptible to oxidative damage by reactive oxygen species, compared to type IIX/B fibers (low oxidative capacity).

KEY WORDS: Chronic fatigue syndrome - Muscle fatigue - Fast-twitch muscle fibers - Muscle weakness - Skeletal muscle fiber