How Much Exercise Is Enough?

The answer depends on your exercise goal: fitness or health. The two are related but not the same. Fit people, as epidemiological studies have shown, are healthy people with reduced risks of heart disease, hypertension, stroke, and diabetes and a lower mortality rate. Yet it is possible to get nearly all the health benefits of exercise without reaching high levels of fitness.

The ACSM minimum guidelines translate into an energy expenditure of about 1,000 calories a week, an amount that researcher have shown to be beneficial for various populations, including young, premenopausal women.

While half an hour of exercise five days a week is good, working out more often and more intensely can yield more health dividends, including improved muscular strength and endurance. You may also need to exercise longer and harder to maintain a healthy weight and lose excess pounds. According to the Exercise Guidelines for Americans, individuals who’ve lost weight may need to exercise 60 to 90 minutes a day to keep off the pounds. Vigorous physical activity (such as jogging or spinning) burns calories more rapidly per unit of time than moderate activities like walking. It doesn’t matter if you goal is to improve fitness or avoid fatness. The same strategy—regular physical activity—is the key to both.