How to tell when your body needs a break

Story highlights

  • When you exercise, you're causing a bit of trauma to the body
  • If you're not allowing the body to recover, you're causing yourself more harm than good

(CNN)We've all been there: Just when you're getting into the groove of your new workout obsession — wham! Suddenly your knee is killing you, or your quads are hurting in a way that just doesn't feel right. Yep, you've over-worked yourself into an injury — and are suddenly wondering why you didn't take a few more rest days along the way.

    So what gives? First, it's important to understand physiologically, what happens when