Fitness instructor Lisa Stone, ACE, answers!

Your fitness program prior to your pregnancy is more important than your age. If you were physically active before becoming pregnant, then you should be fine to continue working out throughout your pregnancy, barring any complications and, of course, with the approval of your healthcare provider. After your first trimester, you may need to begin modifying your workouts as your growing belly and breasts affect your center of gravity and mobility. Once you hit your third trimester, you may find that you need to reduce the frequency and intensity of your workouts through the remainder of your pregnancy.

During your entire pregnancy, though, be sure to really tune into your body's signals as to when you've had enough exercise. If something causes pain or discomfort, don't do it! Sweating and breathing a little more heavily than usual are fine, but you should still be able to converse. (It's okay to perspire, but it's not okay to pass out!) Drink plenty of water before, during and after your workouts to stay well hydrated and to keep yourself and your baby cool. And, use common sense: On days you feel less energetic, cut back on your workouts; on days you're full of energy, go for it!