To understand how exercise affects the contractile function of dystrophic muscle, we
examined the effect of long-term voluntary exercise on mdx mice and related these effects to
our findings in sedentary aging mice. Although the mdx mouse is the genetic homolog for
Duchenne muscular dystrophy, it does not demonstrate the same progression in limb
muscle dysfunction as Duchenne muscular dystrophy as it ages. We postulated that the
sedentary lifestyle of this animal plays an important role in its minimal phenotypic …