Exercise and preexercise nutrition as treatment for McArdle disease

Abstract

McArdle disease is due to an inborn defect in the muscle isoform of glycogen phosphorylase (or 'myophosphorylase'), the enzyme that catalyses the first step of glycogenolysis. This condition is still not fully understood and, while advances in research would help patients immeasurably, these would also enhance our understanding of exercise metabolism. It has been ten years since the first published report demonstrating the benefits of regular aerobic exercise for these patients. However, misconceptions remain and the value of exercise prescription for McArdle patients is still underlooked. Here we review the role of exercise in McArdle disease with the aim to better inform healthcare professionals and thus better serve the interests of patients. Recommendations for regular exercise together with pre-exercise nutrition in children and adult patients are also provided along with examples of exercise practice and its benefits.