Metabolism's Weighty Role
You would give up just about anything to be the same weight you were when you were younger, right? Believe it or not, you need give up nothing. That is, as long as you keep doing what you've always done—and maybe a bit more.
Although metabolism plays a large role in controlling weight, it can't take all the blame. Genetics play a role, too. But genetics are predetermined, and lifestyle is not.
Metabolism is the amount of energy—in this case, calories—that the body burns to maintain itself. You're always burning calories, even when you're sleeping. Your basal metabolic rate (BMR) is the number of calories your body uses at rest. How many calories you burn depends on your BMR, exercise, and the body's muscle-to-fat ratio. Muscle cells burn more calories than fat cells. Muscular people, with less body fat, have a higher metabolism.
After the age of 45, it is estimated that the average person loses around 1 percent of muscle mass per year. To compensate, you may need to be more active than you once were.
Changing with age
Resting metabolic rate regulates body weight and body composition and daily energy needs. Resting metabolic rate decreases with age in women.
If you consume more calories than you burn, the excess is stored as fat and weight gain occurs. A pound represents about 3,500 calories.
To jump-start your metabolism, you must regain the muscle mass. The most efficient way to do that is regular exercise.