You’ve probably done an intense exercise session and spent the next few days knowing you overdid it.
Maybe you were overly excited about a new workout program or you took a friendly competition too far.
Your body likely recovered and the muscle soreness faded in a few days. However, in rare circumstances, extremely strenuous workouts can be dangerous and lead to a serious medical condition called rhabdomyolysis.
Extreme soreness and dark urine? Go to the hospital
Sore muscles are normal after a hard workout and usually are not a reason to worry, said Dr. James Mullen, a Marshfield Clinic physical medicine and rehabilitation physician. The pain should fade in a few days if you drink water, stretch and rest.
Sore muscles that don’t recover or get worse after a few days, weakness and dark tea- or cola-colored urine should set off alarm bells. These symptoms may be signs of rhabdomyolysis, which is an extreme response to injured muscle tissue that can affect the kidneys and heart.
“You need to go to the emergency department if you notice these symptoms in the days following a really intense workout,” Mullen said.
Intense exercise breaks down muscle fibers. When too much muscle breaks down, the kidneys can’t keep up with filtering enzymes released into the bloodstream. This is rhabdomyolysis, and it can cause kidney failure and death if it’s not treated. The muscle breakdown also can release a lot of potassium into the bloodstream, which can cause cardiac arrhythmias.
Full recovery is possible with prompt treatment. You will receive IV fluids to rehydrate you and help your kidneys work properly. You may be admitted to the hospital for monitoring or kidney dialysis if your condition is more severe.
Excessive exercise is just one way rhabdomyolysis can happen. Muscle trauma such as a car crash, certain prescription medications and illicit drug use also can cause dangerous muscle breakdown.
Know your exercise limits
“Rhabdomyolysis from exercise is rare, but it’s preventable and serious enough that you should take steps to avoid it,“ Mullen said.
Gradually increase your capacity for intense exercise. Drastic jumps in your training time, speed or weight lifting volume increase your risk for many sports injuries, including rhabdomyolysis.
Use caution in extreme heat. Heat, dehydration and intense exercise are a dangerous mix. Drink plenty of water. Reduce your intensity, take breaks or stop exercising if you feel weak or sick.
Talk to your doctor before starting an intense exercise program if you take certain medications that could increase your risk for rhabdomyolysis, such as high dose statins. Diuretics don’t directly cause muscle breakdown but could increase your risk by causing you to get dehydrated more quickly.
If you train safely, you should be able to avoid dangerous muscle breakdown.