McArdle Disease

It is advisable to seek evaluation when a person experiences muscle pain, intense cramps, or marked fatigue with physical exertion that eases with rest; this pattern may point toward McArdle disease, an inherited disorder of glycogen metabolism in the muscles.

What it is: The body has difficulty using stored glycogen as a source of energy during exercise, which limits muscle performance.

Signs that are usually noticed:

• Early tiredness when starting an activity
• Muscle cramps or stiffness
• Dark-colored urine after intense exertion

Whom to consult? Because of its metabolic and inherited nature, it is usually addressed by endocrinology and genetics, with support from the internist for comprehensive follow-up. In the presence of these symptoms, the advisable course is for a professional to carry out a careful and personalized evaluation.