Delayed Onset Muscle Soreness (DOMS) is that annoying muscle ache and tightness you get after doing exercise, particularly a new exercise or when you push yourself harder than normal.
So what can you do for it, other than tell yourself it's a "good pain"?
What Causes It?
The process behind DOMS is not fully understood. It seems to come after muscles are worked eccentrically (working to control movement as they are lengthened). It is thought that this causes microtrauma to the affected muscles and that the pain therefore arises from this microtrauma and from the body's response to try to repair the muscle and make it stronger.
It tends to be at its worst 24-72 hours following exercise. Over time muscles will adapt to be better able to deal with this load and so DOMS will become less severe and then won't occur until you expose the muscle to a greater level of load.
What Can You Do About It?
DOMS will improve on its own but while it is present it can be quite painful and can limit the function of the affected muscles as well. This can impair your ability to do everyday tasks (ever tried getting on and off the toilet after a heavy leg day?), as well as affecting your performance in sport.
A recent review showed that soft tissue massage was the only treatment which had scientific evidence showing it reduced pain and improved function.
While not having sufficient quality evidence to show that they improve pain and function, other treatments that are probably effective in reducing DOMS include stretching, contrast baths, foam rolling, and good hydration/nutrition practices.