Sveen ML et al. (2008) Endurance training improves fitness and strength in patients with Becker muscular dystrophy. Brain [doi:10.1093/brain/awn189]

Previous studies in a mouse model of dystrophinopathy have indicated that exercise might induce muscle damage and accelerate disease progression in this setting. On the basis of these findings and clinical experience, individuals with Becker muscular dystrophy (BMD) are advised to avoid excess physical exertion. Sveen et al. have performed the first study to date that has thoroughly investigated the effects of moderate exercise in patients with BMD.

This study enrolled 11 men with BMD and 7 healthy, sedentary controls. All participants took part in 50 training sessions over a period of 12 weeks. Training comprised 30-minute sessions on stationary cycle ergometer at a heart rate corresponding to 65% of maximum oxygen uptake.

The 12-week training regimen improved fitness in patients with BMD (P <0.005); this effect was sustained in the six patients who continued training for 1 year. All participants showed an increase in strength in the muscle groups involved in cycling. There was no increase in levels of plasma creatine kinase—an indication of muscle damage—in the patients with BMD, nor were there any significant changes in muscle morphology. The majority of patients with BMD reported an improvement in physical endurance, leg muscle strength and walking distance after the 12-week training period.

The authors conclude that moderate exercise does not cause muscle damage and is a safe and effective way to produce a long-term increase in fitness in patients with BMD.