People who engaged in moderate activity -- the equivalent of walking for 30 minutes a day for five days a week -- lived about 1.3 to 1.5 years longer than those who were less active. Those who took on more intense exercise -- the equivalent of running half an hour a day five days every week -- extended their lives by about 3.5 to 3.7 years, the researchers found.
The findings show that even for people who are already middle-aged, exercising more can add years to their lives, Franco said.
And how much time do you use doing the exercise that extends your life? About 5,000 hours over 40 years. Put another way, every waking hour spent exercising adds a little less than two hours to your life.