Physical activity
A low level of physical activity is one of the most important factors in the high and rising rate of obesity in the United States. People are simply not getting enough exercise.

Becoming physically active can have a tremendous impact on your total daily energy expenditure. For example, a sedentary person burns just a few hundred calories above his or her resting metabolic rate while going about daily activities (performing household chores or walking to the mailbox, for example). (see our section on Metabolism for more information).

Someone who exercises regularly at a moderate pace doing light gardening or yard work, walking, or dancing can burn an additional 150 calories per half hour—and build muscle mass.

Exercises that build strength also raise the resting metabolic rate because muscle requires more energy for maintenance.