Muscular dystrophy and exercise

What is Muscular Dystrophy? 
Muscular dystrophy (MD) is a collection of diseases that cause progressize loss of muscle mass and weakness. It occurs when mutated, abnormal genes disrupt the production of dystrophin, a protein that is needed to build muscle tissue. There are many different forms of MD and unfortunately there are no known cures. 

The main symptom that is present across all forms of MD is muscle loss and weakness over time, although the age and specific muscle groups this begins in, varies greatly. There are several types of MD, but the most common is Duchenne Muscular Dystrophy, it occurs predominantly in males and symptom onset will usually begin in early childhood. The most common symptoms include;

• Delayed growth
• Regular falls
• Difficulty running, jumping or rising from sitting
• A waddling gait and often walking on their toes
• Enlarged calf muscles and forearms
• Muscle pain and stiffness

Effects of Muscular Dystrophy
It has been reported that people with MD lose 11-55% of their muscular strength, when compared to those without MD. As the essential protein Dystrophin is absent, it means that muscle tissue cannot repair itself to rebuild, having severe consequences on their overall health long term. Some of these long term effects can include; 

• Gait - they will often have difficulty walking due to the muscular strength, endurance and balance required to do so, which results in a wheelchair being required to mobilise. 
• Respiratory function - Progressive muscle weakness can affect the muscles associated with breathing over time, which can lead to the use of a ventilator. 
• Cardiac function - As the heart is a large muscle, weakness to it can reduce cardiac efficiency and output. 
• Swallowing difficulties - If the muscles associated with swallowing/ digestion are too weak, nutrition problems can arise. 
• Scoliosis - when stabilising muscles around the spine are weakened it can cause excessive curvature as they cannot accommodate the load. 
• Difficulty using upper limbs - As muscles in the shoulders and arms are affected, the use of one's arms can be severely limited, making day to day activities difficult.

How can exercise help? 
Exercise is an effective and accessible treatment option for people with MD. Tailored and specific exercise prescription is safe and can help to counteract muscle loss through increased strength and muscle mass. This assists in delaying the progression of MD and maintaining independence and physical function long term. Exercise has been shown to; increase joint stability, coordination, balance, muscular strength and endurance, fatigue levels, quality of life and mental health. It is recommended to seek exercise therapy as early as possible once diagnosed with MD. 

What type of exercise is best? 
For aerobic based exercise low impact and low intensity forms are best. This could include gentle walking, cycling or swimming, focusing on keeping them at a low-intensity level. To use a simple guide, if completing aerobic exercise with MD you should be able to hold a conversation without becoming breathless, if you are not able to, you are most likely working too hard. 

For strength training low load and high repetition should be the focus, starting small and very gradually building up. As muscle mass and strength will not increase at the same rate as those without MD it is important to not overdo it with strength training. 

Stretching is also beneficial for maintaining joint range of movement and preventing stiffness. Being mindful to not over extend through a stretch as this with MD can be hypermobile in some joints due to the lack of muscle mass surrounding them and adapted movement patterns. If you have difficulty stretching, having someone assist you with these movements can also be beneficial. 

​If you would like more information about exercising with Muscular Dystrophy or to chat about seeing one of our Exercise Physiologists, please get in touch at [email protected]

Written By, 

Aleisha Michael 
Accredited Exercise Physiologist.