There’s a big difference between pain and discomfort. The idea that you need to workout to where you’re feeling excruciating pain is not true. No pain, no gain means you need to feel the muscle burn, but you don’t have to have exercise actively hurt to be good for you. In fact, if it does “hurt” you’re probably doing something wrong.

Delayed onset muscle soreness indicates a good workout, but this is different than damage from gross inflammation and tears in the elastic tissues that surround muscle fibers. The former leads to muscle growth, while the latter leads to possible atrophy due to not being able to work out for a while. The average person usually doesn’t don’t toss enough weight for this to be an issue, but sloppy form or coming back from a long bout of inactivity when muscles are deconditioned can also be a culprit, so be careful.

Some will say that the body’s adaptation to stress and discontinued discomfort is a good thing and that progress will keep going. However, the reverse seems to be true both in both scientific tests and field experience, as adaptation has been shown the number one killer of progress in muscle growth or weight loss. Positively stressing the muscles through bouts of intelligently planned and increasing intensity is the best way to force muscle growth.

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