DEAR DOCTOR K: I like really intense exercise, so I expect things to hurt when I'm working out. How do I know if I'm pushing myself too hard?
DEAR READER: The expression "no pain, no gain" has misled many an exercise enthusiast. The fact is, pain and other symptoms during exercise are not normal. You should pay attention when your body is sending you warning signs. Let's start with what you should expect. At the height of a workout, you should be breathing a little harder. You should still be able to talk, but you shouldn't be able to sing. You should feel your heart beating faster than normal during exercise. And you may feel your muscles burn a little as they work hard for you.