What Causes Muscle Soreness?
What Causes Muscle Soreness?
Delayed Onset Muscle Soreness (DOMS) is a common yet unforgettable pain and stiffness that haunts you days after your workout. DOMS can occur anywhere in the body that has recently been exposed to unfamiliar or intense physical activity. Symptoms of DOMS can be local muscle pain, tenderness to the touch, stiffness of the joint, reduction in a joint’s range of motion, and temporary reduction in strength of the affected muscles. Delayed soreness develops within the first 12-24 hours and peaks at around 48-72 hours after exercise.
DOMS can be caused by Intense exercise that uses muscles that are not used to the high demand of work placed on them. Additionally, Eccentric (lengthening) muscle contractions increases chance for DOMS more than concentric muscle contraction (Eccentric- lowering phase of bicep curl, Concentric- upward phase of bicep curl).The severity of soreness depends on the types of forces placed on the muscle. A higher number of repetitions will cause more damage and soreness than a low number of repetitions.
The biggest misconception about DOMS is that it is caused by lactic acid staying within the muscle for extended periods of time. Lactic acid DOES NOT cause DOMS. I remember playing travel baseball all through middle school and high school. We would play 5-8 games every other weekend during tournaments. The Monday after every tournament, our head coach would make anyone that pitched in the tournament run for 30 minutes at the beginning of practice to “flush out the lactic acid.” Lactate is removed from our system, on average, within 60 minutes of stopping the production of lactate. Some studies have actually found that lactate actually helps with cardiac energy production. If we know anything about swimming, we know that our cardiac muscles are crucial.
What actually happens is that there is structural microscopic damage to muscle fibers and membranes within the muscle.This damage creates tears in fibers and membranes that allows calcium to leak into the mitochondria of the muscle, which does not allow the production of ATP to occur. Why is this relevant? ATP is necessary in any and every muscle contraction, The more the muscle works, the more ATP is needed to keep up with the production of force by the muscles. No ATP = No power from muscle contractions.
Additionally, Buildup of calcium activates protease enzymes which break down cellular proteins and cause an inflammatory response. This inflammatory response calls in macrophages to the damaged site. Macrophages are important cells of the immune system that are formed in response to an infection or accumulating damaged or dead cells. Macrophages are large, specialized cells that recognize, engulf and destroy target cells. It is this accumulation of specialized cells, along with swelling from tissue damage, that push up on our pain receptors that make us feel the “pain” of DOMS.
Lactic acid is vital to aerobic and anaerobic activity, but it is not what causes us to hate ourselves for doing heavy squats the morning after the workout.
Go SMAC!
Julian
