When you’re upright and active, even briefly, your body is at work. “You’re engaging a wide range of systems in your body when you move throughout your day,” says Dr. Charles E. Matthews, who studies physical activity and cancer risk at NIH. “Your muscles are contracting, you’re maintaining your balance, and you’re resisting the force of gravity.”

When you’re sitting, he says, “Muscle contractions go way down, and your body’s resistance to gravity decreases.” When you sit for long periods, your body adapts to the reduced physical demand and slows down its metabolism. When metabolism slows, you burn fewer calories and boost the chance that extra energy will be stored as fat.

The best way to raise your metabolism is simply by  moving. The more you move, the better.

A new study led by NIH’s Dr. Steven Moore looked at data on more than 650,000 adults, mostly age 40 and older. The researchers found that leisure-time physical activity was linked to a longer life expectancy, regardless of how much people weighed.

“We found that even a low level of physical activity—equivalent to about 10 minutes a day of walking—was associated with a gain of almost 2 years in life expectancy. High levels of activity—equivalent to about 45 minutes a day of walking—were associated with a gain of 4 years or more,” says Dr. Moore.

Look for opportunities to be active throughout your day. Get moving as much as you can.