Our lives have become all too sedentary. We have eliminated most of the physical activities that got our blood moving when we were younger and that kept our ancestors fit. It is terrific to bring physical activity back into our lives for four reasons.
Movement burns calories
Every movement you make, whether it is blinking your eyes or lifting a grand piano, burns some calories. The more we move, the more calories we burn.
Regular physical activity boosts your metabolism
Calories are burned more quickly, not only while you are exercising, but also afterward for a period of time.
Physical activity helps preserve your muscle mass
Muscle tissue has a rapid metabolism and is much better than fat tissue at burning off the calories we ingest. If your muscles waste away from inactivity, your body burns fewer calories per hour.
Physical activity helps control the appetite
Twenty minutes of exercise before dinner reduces the appetite slightly. This seems to be particularly true for activities that warm the body, such as tennis, running, or dancing. (Some people experience an increase in appetite after cooling exercises, such as swimming.) Unfortunately, it is likely that overweight people experience less (or even none) of the exercise-induced change in appetite than do normal-weight individuals, so this may be a mechanism that helps people stay thin rather than helping people to get thin.8
There are numerous other benefits of physical activity, from reduced risk of heart disease and cancer to more energy and a more relaxed outlook on life. You may find that you will sleep more soundly when your body is tired from exercise. In turn, better sleep makes you feel like taking care of yourself. Chronically tired people prop themselves up with all sorts of indulgences, including unhealthful foods, that do not seem so important when they are well rested.