by Marty Copeland

Why is muscle a must? Because a lean, toned body looks great? Well, many people think so, but that is a matter of opinion. Muscle is valuable for many reasons, including its ability to burn calories. In fact, one pound of muscle burns about 35 calories a day, whereas one pound of fat burns only 2 calories.

Studies tell us that between the ages of 20 and 30, without weight-resistant exercise, we begin to lose muscle. As we age, the rate at which we lose seems to increase slightly. As we lose muscle, our basal metabolic rate slows down, which means we are burning fewer calories. This change in metabolism generally means a gain in fat. Let's say that between the ages of 30 and 40, we have lost 10 pounds of muscle and gained about 10 pounds of fat. That means that in 10 years, we would have a 20-pound body composition change and still weigh the same amount.

There is another interesting aspect to muscle. Muscle is denser and takes up much less space than fat. You could therefore maintain the same weight you are now and be 2 sizes smaller by gaining 10 pounds of muscle and losing 10 pounds of fat. Just think, by increasing your muscle, or your lean body mass by 10 pounds, you would increase your metabolic rate by about 350 calories a day. Just gaining 5 pounds of muscle would increase your calorie expenditure by 175 calories a day. That's 63,875 calories or 18 pounds a year.

No wonder as we age it is so easy to gain fat simply by not exercising. Many people are frustrated by the fact that they eat just as they always have, but now they are gaining weight, not realizing that each year without resistance exercise, their metabolisms are slowing down. Exercise is the only way to reverse this effect of aging.

*Many people, especially women, are afraid of getting "too muscley," so they avoid strength-training exercises altogether. I know because I used to be one of those people, but that was before I discovered that muscle not only makes you feel better and look more toned, it also greatly increases your body's ability to burn fat. After so many years of starvation dieting, my metabolism needed to be raised from the dead. It seemed as though it was impossible for me to lose weight and keep it off. Replacing lost muscle was crucial to reaching and maintaining my weight-loss goals.

Now, don't worry about looking like the Incredible Hulk. You won't. You'll just look fit because that's what you'll be—FIT! Embark on this strength-training program and watch your body composition start changing.

From improving how we feel, how we look, and how we think to increasing our life expectancy, the ability to exercise and literally change the quality of our lives is something we should be thankful for. Exercise is not only an anti-depressant, but it increases the quality of our sleep. Another one of its greatest benefits is that it's never too late to start! Even beginning an exercise program in our later years can greatly improve our health and mobility. It is vital that we continue to use our bodies so that we don't lose our physical capabilities. We should plan on growing old well able to enjoy an active lifestyle!

Not only does weight training reduce your blood pressure, lowering your risk of cardiovascular disease, but a landmark study performed by researchers at the USDA Human Nutrition Research Center at Tuft's University revealed that weight training has a tremendous effect on aging. In only 8 weeks, 10 frail men and women between the ages of 86-90, all of whom had chronic diseases or disabilities, increased the strength of their leg muscles by a dramatic 174 percent without any injuries! They also increased their balance and walking speed.

According to the American College of Sports Medicine, weight or resistance training is the only type of exercise that can substantially slow and even reverse the declines in muscle mass, bone density, and strength that were once considered inevitable consequences of aging.