WE ALL KNOW that regularly getting to the gym or repeatedly putting in any type of physically taxing exercise can improve a whole host of health markers and reduce the risk for lots of different diseases, from diabetes to heart disease. But a new study from Brigham Young University has discovered that high levels of physical activity may actually make our cells appear to be about nine years younger than those in couch potatoes.

Researchers looked at data that measured telomere length in cells from over 5,000 people enrolled in the National Health and Nutrition Examination Survey. Telomeres are the protein end caps on our chromosomes, and the longer they are, the younger they are as the tips get broken off bit by bit as each cell replicates. The survey also included information on how many activities the subjects participated in over 30 days, which let the scientists figure out how much physical activity they were getting.

They found that sedentary people, and even those who had low to moderate activity, had the shortest telomere length, while those with the highest levels had significantly longer telomeres. The study defined high physical activity as the equivalent to running for 40 minutes, five days a week.

“If you want to see a real difference in slowing your biological aging, it appears that a little exercise won’t cut it,” said study co-author Larry Tucker, Ph.D., an exercise professor at BYU. “You have to work out regularly at high levels. We know that regular physical activity helps to reduce mortality and prolong life, and now we know part of that advantage may be due to the preservation of telomeres.”

If you are up for keeping your cells younger and preventing telomeres from deteriorating too soon, why not hit up one of our highly challenging and intense workouts. Along with building lean muscle, looking better, and improving health, you may just be giving your cells a dose of youth-regenerating power.