They say all work and no play makes a person boring and unhappy, but now researchers believe that it may affect how long they live. That is because a new study sponsored by the National Institutes of Health (NIH) has determined that people who take part in regular amount of leisure-time physical activity may increase their life spans by as much as 4.5 years. This phenomenon was seen irregardless of a person's body weight.

Currently the U.S. Department of Health and Human Services recommends that adults (ages 18-64) take part in physical activity on a regular basis, which translates into 2.5 hours each week of moderately intense exercise, or 1.25 hours of vigorously intense exercise. Moderately intense exercise is defined as activity whereby a person can talk but not sing. Vigorously intense exercise is when a person can only manage a few words without stopping to breathe.

In the study in question, published online in PLoS Medicine, researchers looked at over 650,000 adults, a majority of whom were 40 years of age or older. According to the data, when a person got the recommended amount of exercise, their life expectancy increased by 3.4 years. When they took part in twice the recommended level of activity, their life expectancy increased to 4.2 years.

In other words, more physical activity was linked to greater longevity. Even low levels of exercise had benefits, whereby just half the recommended level of activity led to a more modest increase (1.8 years), though an increase nonetheless. The benefits held true even when accounting for such factors as body weight, gender, and race. In fact, even when a person was obese, some level of activity helped to temper the negative health effects of being overweight. Finally, the correlation between physical activity and longevity was stronger among those individuals who had a history of cancer or heart disease than those with no history of these conditions.

The findings represent further support for the health benefits of exercise, which is something health experts have been encouraging for years. After all, being active benefits our health in a number of ways. Exercise helps us maintain a healthy body weight, strengthen our bones, muscles, and joints, and has tangible benefits on our psychological and emotional health. It is also believed to reduce our risk for certain disease, including heart disease, stroke, and certain cancers.

When done properly, exercise is also a great way to have fun, get some fresh air, and even meet new people who share common interests. Combined with a wholesome diet, exercise can be an important part of a healthy lifestyle.

Before beginning any exercise regimen, consult with your physician or an experienced trainer. To learn more about the importance of exercise, talk to you doctor or visit the website for Center for Disease Control and Prevention (CDC).