What Exercises Are Safe for Duchenne Muscular Dystrophy?

It is entirely natural to want your child to play, stay active, and just be a kid. Children with Duchenne muscular dystrophy (DMD) can and should participate in physical activities, but it is crucial to choose the right types of movement. Because of how DMD affects the muscles, certain high-impact activities—like jumping on a trampoline, running downhill, or maximal heavy lifting—can cause faster muscle breakdown and should generally be avoided ^[1]. Instead, the safest approach involves submaximal, low-impact, and low-resistance activities selected for your child’s specific abilities and performed under individualized guidance ^[2].

Before starting or changing an activity, always review the plan with your child’s neuromuscular team. Safety depends heavily on your child’s walking ability, fatigue levels, steroid use (which can affect bone strength), and their current cardiac and respiratory health.

Understanding Muscle Stress in DMD

In a healthy body, a protein called dystrophin acts like a shock absorber, protecting muscle cells from the mechanical stress of movement. Children with DMD lack this protective protein, which destabilizes the muscle cell membrane ^[3]. As a result, physical stress can cause repeated injury and inflammation, eventually leading to muscle tissue being replaced by fat and fibrosis (scarring) ^[3].

When physical therapists talk about safe movement for DMD, they often look at the type of muscle contraction as a general principle:

• Eccentric contractions happen when a muscle lengthens while braking or absorbing force—such as walking down a steep hill or landing from a jump. For muscles lacking dystrophin, heavy eccentric stress forces the muscle to take on a load it cannot safely handle, leading to accelerated breakdown and persistent damage ^[1].
• Concentric contractions happen when a muscle shortens as it works—such as pulling an arm through the water or pedaling a bike on a flat surface. These movements are generally lower-risk because they do not force the fragile muscle to act as a harsh brake.

However, real-world activities use a mix of both. The goal is not just to find perfectly concentric exercises, but to choose lower-risk activities that avoid high impact, heavy resistance, and exhaustion.

Lower-Risk Activities to Encourage

When approved by your care team, these submaximal, low-impact activities are often excellent options:

• Swimming and Aquatic Therapy: Exercising in a pool (hydrorehabilitation) is highly favored for children with DMD ^[4]. The water’s buoyancy supports the body, reducing joint strain while allowing the child to move and maintain aerobic fitness safely ^[4]. Precautions: Swimming requires direct, competent supervision. Fatigue in the water creates a drowning risk, and respiratory or cardiac issues can change what is safe for your child. Always ensure safe pool entries, exits, and supervised transfers.
• Cycling on Flat Ground: Using a standard bicycle or an ergocycle (stationary bike) on flat terrain can be a great way to stay active ^[5]. Precautions: Ensure the resistance is kept very low, plan for balance and fall risks, use a helmet or adaptive equipment if needed, and incorporate frequent rest breaks.
• Walking on Level Surfaces: Normal walking at a comfortable, conversational pace helps maintain mobility. It is vital to stop before your child gets unusually tired.

Activities to Avoid or Modify

Activities that involve heavy eccentric loading, high impact, or pushing to exhaustion pose a higher risk of muscle damage ^[1]. Generally, avoid:

• Trampolines and Bouncy Castles: The repetitive, high-force landings are extremely stressful on dystrophin-deficient muscles.
• Running Downhill or Stairs: Modest stair practice prescribed by a therapist is okay, but repeated downhill running or repetitive stair climbing for exercise forces heavy, damaging eccentric braking.
• High-Load Resistance Training: Maximal, heavy, or “to-failure” weightlifting should be avoided. (Note: Carefully prescribed, very low-load strengthening might be appropriate for some, but only under strict guidance from a neuromuscular physical therapist ^[2]).
• Aggressive Contact Sports: These pose high fall risks and unnecessary physical impact.

Stretching and Positioning

As muscles weaken, children are at high risk for developing contractures—a condition where muscles and tendons tighten, which limits joint range of motion and makes walking significantly more difficult as the disease progresses ^[6]. Contractures commonly affect the ankles, knees, and hips ^[6].

A customized, daily stretching routine prescribed by your physical therapist is an important tool to help manage and delay contractures.

• Stretches must always be gentle and pain-free.
• Never force a stretch or use bouncing movements.
• Your therapist may also recommend specific positioning guidelines or night splints to help maintain flexibility.

School PE and Inclusion

Children with DMD should absolutely be included in school life and Physical Education, but accommodations are necessary. Work with the school to modify timed races, eliminate repeated stair-climbing, and provide safe, enjoyable alternatives to contact sports. For nonambulatory children, activities can be adapted to allow seated or supported movement, or the use of their mobility device. Emphasize energy conservation: your child should always be allowed to rest, take frequent breaks, and stop immediately if they feel tired or in pain, without pressure to keep up with peers.

Warning Signs: When to Stop and Seek Help

A practical way to monitor activity is to ensure your child can maintain a normal conversation while playing. Stop the activity well before exhaustion. If your child has persistent next-day weakness, worsening gait, cramps, unusual breathlessness, or a longer-than-usual recovery time, the activity was likely too intense.

🚨 URGENT CARE WARNING: Rhabdomyolysis
If your child develops dark, cola-colored urine after an activity—especially if accompanied by severe muscle pain, significant weakness, swelling, or reduced urination—this can be a manifestation of rhabdomyolysis (rapid, severe muscle breakdown) ^[7]. Do not wait for a routine appointment. Stop the activity and seek urgent same-day medical or emergency assessment. While dark urine can have other causes, it must be evaluated immediately by a doctor to protect the kidneys and manage the muscle damage.