Shaping Up Part 3

Everybody needs an inspiration before they make a big life change, and that was Kathy Mann's situation. She weighed 360 pounds.

She was a diabetic and had suffered a heart attack, but it was the thought of those wedding pictures that finally did it.

"I was very unhappy with myself," she said. "I couldn't find clothes to wear, and my kids were getting ready to get married. I knew they were going to get married soon, and those pictures were for life and I didn't want to be this big thing in all of their wedding pictures. So, I started working on it, and with each wedding I got a little thinner."

Kathy had tried different diets and pills over the years, and none of it had ever worked for her. This time, though, she avoided the gimmicks and got moving. She began to walk more. She went to a gym and asked for help. She chose a weight-loss program she was comfortable with -- and it worked!

Kathy Mann lost 160 pounds over seven years. Today, she feels better, she's a lot happier with the way she looks, and she's motivated to maintain the weight loss.

"I always take the steps at work," she said, "and try to move and then I go to the gym."

"People tend to think of a diet as a food-oriented activity, but probably one of the best things that people can do is not a food-oriented activity but an exercise-oriented activity," Mann said. "So No. 1, keep moving, exercise."

Losing weight is all about numbers, according to health experts. A pound of fat represents about 3,500 calories of stored energy. To lose a pound, you have to burn off 3,500 more calories than you consume. If you exercise 500 calories a day, that should add up to a pound of weight loss a week.

There are lots of ways to do that. Ninety minutes of walking slowly, 45 minutes of jogging, 40 minutes of swimming, you could go to the gym and spend 40 minutes on a stationary bike, or you can find some friends and play basketball for 50 minutes.

Health experts say you don't have to do it all at once. You can spread your exercise out over the day to get the same benefits.

Washington, D.C., nutritionist Katherine Tallmadge recommends yoga that you can do at home, because it cuts down on stress and keeps calories burning.

"Even just 15 minutes in the morning, you can burn enough to lose 15 pounds in a year," she said. "You don't have to spend two or three hours at the gym every day."

Choose an exercise that's right for you -- something you can stick with for a long time. And if you're just starting out, go slowly. You don't want an injury to set you back.

Building muscle is also important, because muscle burns calories and body fat does not.

Fitness expert Erin Demaranis recommends that you combine cardiovascular exercise, like running or cycling, with moderate weight training to build muscle and to rev up your metabolism long after your workout is over.

There are those people who exercise every day and still find it hard to get the body they want. Demaranis said you want to find the right combination of exercise and diet for your body.

"It's not only the cardiovascular, but it is the weight training and it is the nutrition," she said. "Nutrition kind of gets lost in all of it, 'Well I'm going to work out, I can eat whatever I want.' Well, nutrition is really key, especially when it comes to a flat stomach."

Kathy Mann knows that exercise works. It wasn't easy getting started, but now it's a regular part of her life, for the rest of her life.

"God knows I've tried everything there is to try," Mann said, "but I really believe it's you. You have to want it and you have to work at it."

Maybe you're thinking that exercising 500 calories a day sounds like more than you can handle with your busy schedule. And that's understandable. So, go back to the math. Exercise half that much every day and cut back 250 calories every day to get the same weight loss result -- a pound a week; 52 pounds in a year.

Whatever you decide, be sure your plan includes some exercise.