Benefits of Exercise
Exercise has traditionally been discouraged for people with muscle disorders including MD out of fear of worsening symptoms. Various forms of exercise and physical therapy have been used to treat Muscular Dystrophy for a number of years. However, available evidence has lacked the necessary consistency to define exercise intensity, duration and frequency.
Limited studies have assessed exercise training including:
- Aerobic training at 60-80% peak heart rate, for 20-40 minutes at three times per week, and
- Strength training at variable intensities for two to three times per week. Studies have shown that low-intensity aerobic training improves peak exercise capacity with no signs of muscle damage in Facioscapulohumeral Dystrophy (FSHD), Becker's and Myotonic Dystrophy.
Moderate intensity strength training has shown no negative effects, however improvements in muscle strength or size are limited or non-existent. The application of neuromuscular electrical stimulation, as a substitute for strength training, has recently been reported to result in improved muscle strength in FSHD.
In 2010, researchers (in a Cochrane review) examined the safety and efficacy of strength and aerobic training in neuromuscular diseases including MD. In all, 36 studies were included in a meta analysis. The review found that strengthening exercises at a moderate intensity did not worsen disease progression. It should be noted that studies reviewed lacked randomization and several studies also grouped different neuromuscular conditions / diseases together making it difficult to draw conclusions about Individual’s responses to exercise.
Sveen et al. performed research that investigated the effects of moderate exercise in individuals with BMD. Seven men with BMD participated. They engaged in training (50 sessions) over 12-weeks. Training included 30-minutes using a stationary cycle ergometer at a heart rate corresponding to 65 percent of maximum oxygen uptake.
Study results showed improved fitness for the individuals with BMD (P<0.005). Sustained results were reported by six participants that continued to train a year after the initial sessions. Participants showed increased strength in muscle groups used in cycling. There were no increases in plasma creatine kinase, which can indicate signs of muscle damage.
After the 12-week period, participants reported improved physical endurance, leg muscle strength, and improved walking distance after training. Though limited in sample size, the study suggests 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.
A review of literature also shows that Qigong may be a beneficial exercise for individuals with MD. Qigong is an ancient Chinese system of postures, exercises, breathing techniques, and meditations. Qigong has been found to improve cardiovascular, respiratory, circulatory, lymphatic and digestive functions. Studies show that Qigong training reduces pain and improves sleep, and physical functioning in individuals including individuals with MD.
A review of existing research shows that more research is needed to develop optimal exercise guidelines for people with MD. Exercise can have benefits for Individuals with Muscular Dystrophy including but not limited to:
- Maintenance and improvement in muscular strength for performing activities of daily living (ADLs) such as stair climbing;
- Slowing the rate of increased weakness or contracture development which can prolong ambulation, and
- Support maintained of sufficient respiratory capacity, and
- Strengthening postural muscles, which can slow the formation of scoliosis.