Ask any gym rat about muscle soreness after a hard workout and you might hear something about lactic acid. It's been a commonly accepted wives tale for years that the build up of lactic acid in muscles causes fatigue and soreness.

The truth is that muscle soreness, (the kind that sets in 24-48 hours after a hard workout) is really due to microscopic muscle tears. The microscopic tears that occur as a result of over exertion actually swell and bleed, and cause an increase in sensitivity.

When you work so hard that you tear down muscle cells, the body responds by building up new muscle that can do that same amount of work the next time and not suffer damage. This is why you get stronger, and also why doing the same activity after a while no longer leads to muscle soreness or an increase in strength. Your body has an amazing ability to adapt to the task at hand.

If you want to limit the amount of muscle soreness you experience after a hard work out, try the following:

hot baths
extended pre workout warm ups

You can also limit muscle soreness by slowly increase the weight you are lifting or the work that you are doing. Sticking with an increase of less than 10% per week allows the body to build strength without producing lots of micro tears in the muscle fiber.