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When muscle tissue is injured by exercise, the fibers tear. Ideally, in a day or two the fibers repair themselves and are stronger than before. This is the basis of building muscle, and some muscle soreness after a workout—especially during the first few weeks of intensified activity—is to be expected. It’s totally normal for your quads and glutes to ache after the first hilly run or ride of the season, for example.
But if your muscle soreness is intense and doesn’t begin until 24 to 48 hours after the muscle injury, you may have a serious condition called delayed-onset muscle soreness (DOMS). It can happen when you apply an excessive loading force to muscle cells. It’s important to distinguish the symptoms of DOMS from the everyday aches and pains that come after hard exercise. This pain can be severe.
Why is DOMS serious? When muscle tissue is injured, a process called rhabdomyolysis causes it to release a protein called myoglobin. We all have a bit of myoglobin released after hard athletic events, and some of it is processed by the kidneys. Several studies that looked at healthy athletes after marathons found mild to moderate amounts of myoglobin in their urine, a condition called myoglobinuria.
When the muscle injury is more serious, however, the amount of myoglobin can be quite large. The urine can be a dark color, and in some cases kidney damage and even kidney failure can result.
Normal post-workout soreness:
Hydrate, fuel up, sleep well. Give your body the best opportunity to repair muscle damage and come back strong. Drink fluids until your urine is clear, eat smart and get a great night’s sleep. The best restoration and recovery happen while you sleep.
Try an NSAID. An anti-inflammatory like ibuprofen or naproxen can help alleviate soreness.
Delayed-onset muscle soreness:
Hydrate and see your doctor. If you suspect you have DOMS (severe muscle pain and soreness that came on 24–48 hours after hard activity, and dark urine), start drinking lots of fluids and call your doctor. A sports doctor is a better bet than a primary care physician because he or she will have more experience identifying DOMS.
Your doctor will do a urinalysis to check your myoglobin level and, if necessary, perform blood tests to determine if there’s been any kidney damage. DOMS is much more common than most athletes realize. Why some athletes experience DOMS and others don’t is not yet understood, but one of the most important factors is dehydration before, during and after intense activity. However, regardless of their hydration status, some athletes just seem prone to developing DOMS and get it often, probably because of biological and genetic factors affecting their muscle tissue. The good news: DOMS is usually preventable with education and smart pre-exercise behavior.
Hydrate. Proper hydration before engaging in any exercise or athletic event can help ease common post-exercise muscle soreness and, more important, prevent DOMS. Factors to consider: temperature and humidity level (e.g., Vegas versus Seattle), the intensity of effort you plan on reaching (race versus easy run), and your overall health during the previous week (even a mild stomach bug or case of diarrhea can dehydrate you). Drink enough fluids to keep your urine running clear.
New York City sports medicine specialist Jordan D. Metzl, M.D. is a 33-time marathon finisher and 13-time Ironman. His book, The Athlete’s Book of Home Remedies, has more than 1,000 tips to fix all types of injuries and medical conditions.