Muscle Soreness After Exercise

What is muscle soreness?
Muscle soreness can be alarming and discouraging for new exercisers, but no need to panic.  Delayed onset muscle soreness, called DOMS, or muscle fever, is that pain you may feel a few hours or days after strenuous exercise or performing a new workout your body is not accustomed to.  The soreness is usually felt when the muscle is stretched, contracted or placed under pressure and usually not felt at rest.  It usually subsides 2-5 days after exercise, depending on the level of intensity and muscle damage.  If your pain persists longer than about 7 days or increases despite these measures, consult your physician.

What causes this muscle soreness? 
It is thought to be a result of microscopic tearing of the muscle fibers.  The amount of muscle tearing depends on how hard and how long you exercisesd and what type of exercise you performed.  Swelling in the muscle from the tears may also contribute to soreness.  Eccentric muscle contractions, when your muscle is contracting while lengthening, seems to cause the most soreness.  Examples of eccentric movements are when you lower your weights, lower into a squat, run downhill, or when you go down stairs.
How do you prevent muscle soreness? 
It can be reduced or prevented by gradually increasing the intensity of a new exercise program. Soreness can theoretically be avoided by limiting exercise to concentric and isometric contractions, but eccentric contractions in some muscles are normally unavoidable during exercise, especially when muscles are fatigued.  Stretching or warming up the muscles don’t necessarily prevent soreness and if you overstretch a muscle, especially if it is not warmed up, this can be the cause of some soreness.
How do you treat muscle soreness?

Nothing is proven to be 100 percent effective, however, there are a few ideas.  You may want to increase the blood flow to the muscle with a massage, hot bath, or sauna.  Ice can provide some relief to sore tendons by delaying the inflammatory response and decreasing swelling to a degree, but in the long run heat would be better on a repetitive basis to enhance the blood supply.  One technique I frequently use to reduce my own muscle soreness is to use a foam roller for my own self massage.  Also, continued light exercise the following day may actually temporarily suppress the soreness.   Some literature state that exercising sore muscles appears to be the best way to reduce or eliminate the soreness, but this has not yet been systematically investigated.