Exercise can often leave your muscles feeling tired and sore. This postexercise discomfort is called Delayed Onset Muscle Soreness, and it can affect any of your muscles. Delayed onset muscle soreness is especially problematic when it affects your legs as it can make walking, sitting and even sleeping uncomfortable. There are several theories as to what causes DOMS, although one single unifying explanation has yet to be identified. Most experts agree that micro muscle trauma is one of the most likely candidates.
Too Much, Too Soon
A sudden increase in workout intensity or volume is a sure way to trigger a painful attack of delayed onset muscle soreness. Excessive exercise may cause microtraumas in your muscle tissue which results in inflammation, swelling, stiffness and pain. In this instance, the best way to avoid DOMS is to gradually increase exercise intensity and duration over several weeks so you do not "shock" your muscles too much.
Doing Something New
Another cause of muscle microtrauma is doing a new exercise that uses your muscles in a way that they are not accustomed to. For example, if you normally do squats but, for a change, do lunges instead, your muscles may feel sore the next day. To avoid this, introduce new exercises into your workouts gradually and allow for a transition period of a few weeks so your muscles can get used to the new exercise.
Muscles generate force as they shorten and also as they lengthen. The shortening phase of an exercise is called the concentric contraction, while the lengthening phase is called the eccentric contraction. The eccentric contraction causes the greatest muscle microtrauma and therefore has the greatest potential for causing DOMS. Lowering your weights very slowly or running downhill and braking to decelerate are both activities that are likely to cause significant DOMS.
Prevention and Cure of Muscle Soreness
If you have had a prolonged break from exercise or are just starting a new workout routine, some delayed onset muscle soreness is all but inevitable. You can, however, take some steps that may reduce the severity of your discomfort. Always warm up before and cool down after your workout and consider taking a cold bath or alternating hot and cold showers once your workout is complete. Cryotherapy in the form of ice packs applied to sore muscles may also help. Staying active between workouts by walking and performing light exercise can reduce the severity of your soreness.