Not true. Training, no matter how intense, should never actually hurt. Pain is not an expected, acceptable result of exercise or of a training program - and it should not be ignored.

You Have to Break Down Muscle to Build Improvement

Not true. Muscle breakdown, know as "mircotrauma," is a result of excessive working of the muscles such as in strength training. But it is not a necessary precursor of developing muscle strength and resistance.

Athletes Should Go for the Burn

Not true. The burning sensation athletes experience in muscles - most likely related to increased levels of lactic acid - is unrelated to increased levels of lactic acid - is unrelated to improvement of performance.

Muscle Turns to Fat and Vice Versa

Not true. Fat and muscle are separate, highly specialized kinds of human tissue. Ceasing, or launching, an exercise program will lead to gains or reversals, but one doesn't "turn into" each other.