Rotterdam: Regular exercise that keeps you fit can prolong life by up to four years, according to new research from the University of Erasmus.

Researchers examined the medical records of 5,000 middle-aged and elderly Americans to discover that those who took moderate exercise on a regular basis lived 1.3 to 3.7 years longer than those who didn’t take any. Those who took part in strenuous daily exercise such as jogging increased their lifespan still further from 3.5 years to 3.7 years. The findings are published in the Archives of Internal Medicine.

Oscar Franco, one of the researchers said: “This shows that physical activity really does make a difference – not only for how long you live but for how long you live a healthy life.”

The effects of how low, moderate or high levels of physical activity, affected lifespan were calculated, taking into account age, sex, whether people smoked or had health problems.