If you have just begun a fitness program, or perhaps started up again after a long holiday break, you may have become really sore after exercising. You are probably experiencing delayed-onset muscle soreness (DOMS). Is this discomfort a necessary part of exercising? Get the scoop from two experts at the University of New Mexico, Albuquerque—Johndavid Maes and Len Kravitz, PhD.

#1: What Is DOMS? DOMS is the
perception of pain and discomfort following exercise that involves increased intensity; longer duration; unfamiliar movements; or eccentric muscular work, such as downhill running or plyometrics. This discomfort is a normal response, and most people experience it to some degree.

#2: What Are the Causes and Symptoms of DOMS? For many years DOMS was blamed on the buildup of lactate (a metabolic by-product produced in the muscles from the breakdown of carbohydrate) after intense workouts, but recent research has demonstrated that the soreness following intense eccentric exercise is completely unrelated to lactate buildup. DOMS is actually brought about through tissue trauma caused predominantly by eccentric exercise. This type of exercise damages the muscle cell membrane, causing inflammation and leading to the formation of metabolic waste products that act as a stimulus to the nerve endings directly responsible for the sensation of pain.

Symptoms of DOMS can include pain, muscle tenderness, stiffness, swelling and loss of strength. Pain and tenderness usually hit the high point 1 to 3 days after exercise and subside within 7 days. Stiffness and swelling can peak 3 to 4 days after exercise and generally resolve within 10 days. Strength loss typically peaks within 48 hours after exercise; full recovery can take as long as 5 days. These symptoms are not dependent on each other and do not always occur together.

#3: What Can Help? Nonsteroidal anti-inflammatory drugs (NSAIDS)—such as aspirin and ibuprofen—were long considered a way to alleviate the symptoms of DOMS, since they were thought to combat the inflammation that occurs with exercise-induced muscle damage. However, because of inconsistencies in the research on NSAIDS and the possible side effects of their use, such as gastrointestinal distress and hypertension, these drugs no longer appear to be the best choice for treating this condition. Employing physical strategies seems to be a more consistent, effective way to keep soreness at a minimum. (See “Physical Ways to Decrease Soreness.”)

Understanding the causes, symptoms and treatment of DOMS may help you avoid its complications—so you can keep exercising!