The effects of concentric and eccentric training in murine models of dysferlin‐associated muscular dystrophy

摘要

Abstract Introduction Dysferlin‐deficient murine muscle sustains severe damage after repeated eccentric contractions. Methods With a robotic dynamometer, we studied the response of dysferlin‐sufficient and dysferlin‐deficient mice to 12 weeks of concentrically or eccentrically biased contractions. We also studied whether concentric contractions before or after eccentric contractions reduced muscle damage in dysferlin‐deficient mice. Results After 12 weeks of concentric training, there was no net gain in contractile force in dysferlin‐sufficient or dysferlin‐deficient mice, whereas eccentric training produced a net gain in force in both mouse strains. However, eccentric training induced more muscle damage in dysferlin‐deficient vs dysferlin‐sufficient mice. Although concentric training produced minimal muscle damage in dysferlin‐deficient mice, it still led to a prominent increase in centrally nucleated fibers. Previous exposure to concentric contractions conferred slight protection on dysferlin‐deficient muscle against damage from subsequent injurious eccentric contractions. Discussion Concentric contractions may help dysferlin‐deficient muscle derive the benefits of exercise without inducing damage.