Described herein are methods of treating muscular dystrophy, including Becker's muscular dystrophy and Duchenne muscular dystrophy. The methods comprise administering a phosodiesterase 5A (PDE5A) inhibitor, such as tadalafil, to a subject in need thereof. Administering the PDE5A inhibitor has beneficial effects such as restoring functional sympatholysis, alleviating ischemic insult to dystrophin-deficient muscle membranes, reducing use-dependent muscle injury, and thus can slow muscular dystrophy disease progression.
