By Lydia Ramsey From Business Insider

Aging is an inevitable fact of life.

But if you exercise pretty frequently and eat right, then you might be a lot younger than you think — at least as far as something called your “fitness age” is concerned.

The “fitness-age calculator,” which determines your fitness age based on how physically fit you are — rather than how many years you’ve been around — was developed in 2013 by researchers at the Norwegian University of Science and Technology.

In 2015, researchers tried out the calculator on athletes competing in the National Senior Games, a massive annual event with over 12,000 athletes 50 and over, competing from July 3 to 16.

While the average chronological age of the participants was 68, their average fitness age was a striking 43, The New York Times reported.

The calculator works by taking information about where you live, your age and gender, how frequently you exercise, your heart rate, and your height and waistline measurements.

Then, using these variables, the calculator comes up with something called your VO2 max, a measure of how much oxygen your body can take in, measured in milliliters of O2 per kilogram of body weight per minute. While your VO2 max is influenced by your age and gender, it’s largely determined by your workout regimen. Generally speaking, the more you exercise, the more oxygen your body can absorb.

What can your fitness age tell you about your health?
At its core, the calculator shows that as long as a person is not overweight and exercises regularly, then the chances of getting sick and dying at an earlier age lessen, said Dr. Amy Ehrlich, a geriatrician at the Albert Einstein College of Medicine.

According to a Gallup survey, about 28% of people in the US are obese, and 35.6% are considered overweight. So a majority of Americans who try out the calculator would probably get a fitness age that’s higher than their actual age.

In people older than 65, regular exercise has been found to help stave off a host of diseases, including colon cancer and depression. And it’s never too late to start, Ehrlich said. People who begin exercising as late as 85 can drastically improve their health, she said. Of course, you should consult with a health professional about what types of exercise to engage in to be sure that you don’t overdo it.

We gave it a try — and got some good news
I tested it out: I’m a 23-year-old woman living in New York City, and I exercise for at least 30 minutes about two to three times each week. After popping this information into the calculator, as well as some educated guesses about my waistline and resting pulse, it told me that I had the fitness age of under 20 years old, the same result I got last year when I tested it out as a 22-year-old. Oh, to be a sophomore in college again!

To see how weight gain could affect my fitness age, I increased my weight by 70 pounds and upped my waistline size by 10 inches. Surprisingly, my fitness age went up to only 22, likely because I didn’t change how much I was exercising. When I changed my response for working out to “almost never,” my fitness age jumped up to 40.

Getty Images 454940855Joe Raedle/Getty Images

See how your fitness age compares to your real age by visiting the web site link below

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