I have always been quite thin and have never worried about my figure. I'm 22 now and I notice my body becoming very flabby. I eat right but do not exercise. I am not overweight. I am 5'5" and weigh 110 pounds. What exercises should I start out with?

Sarah

You've just outlined one of the most important reasons for exercising, Sarah. Eating right is not enough if you want to maintain a lean physique. Thinness is no indication of fitness or good health, either. At 5'5" and 110 pounds, you're certainly in no danger of being overweight, but as you mentioned, you're gaining body fat.

I recommend that you start weight training to increase your lean mass. Adding some muscle to your frame will raise your resting metabolism so that you'll burn more calories throughout the day in addition to those you use working out. Another reason to start weight training is that resistance exercises help you maintain bone density.

After age 30 we all begin to lose muscle mass. Unfortunately, women start losing bone density at this age. (Men lose it at a much slower rate until they hit their sixties.) One of the reasons elderly people often break their hips if they fall is due to this loss of density and the weakening of their bones. You have a perfect opportunity to begin a program that will help you stay lean and strong the rest of your life.

If you have no experience at all with weight training, I suggest you take a few sessions with a trainer at a health club or YMCA to learn the basics. After that, you can decide if you want to work out at home, which is convenient, or at a gym, where you'll have company while you're working out. A basic circuit of exercises that includes all the major muscle groups of the body will help you get stronger and leaner.

Do exercises for the front and back of your legs, such as leg extensions and leg curls, if you're in a gym that has these machines. You can also work your quads and hamstrings (front and back of the thighs, respectively) by doing squats and lunges, which can be performed anywhere. Squats and lunges also work your gluteus maximus (butt), an added bonus.

For your upper body, lat pull-downs in the gym or dumbbell rows in the home will train your largest upper body part -- your back. Do presses lying on a bench with free weights, or on a chest machine at a gym, for your pectoral (chest) muscles. Seated overhead presses will take care of your shoulders. The old standby exercises for your arms -- bicep curls and tricep extensions or push downs -- will complete your upper body routine.

If you want to do these exercises properly, it's worth it to take a lesson or two with a trainer. If you want to wing it alone, get "Weight Training for Dummies" by Liz Neporent and Suzanne Schlossberg (IDG Books; www.dummies.com). It's a good beginner's guide to weight training. You can work out with weights two or three time per week, but never two days in a row. Give your muscles a chance to recover and grow.

You don't need cardiovascular exercise to lose weight, but you do need it to have a complete fitness program and be healthy. You should spend 30-45 minutes doing aerobic exercise, four or more days per week. Cardiovascular exercise strengthens your heart, lowers your cholesterol and blood pressure, and increases the amount of energy you have in general. Aerobic exercise will burn some calories, and help you in your quest for a leaner body.

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