When It Comes to Fitness, Your DNA Isn’t As Important As You Think

Even though my sister and I are very similar, the way we sweat has never been the same. She thrives when she’s lifting weights and doing burpees like it’s nobody’s business. I, on the other hand, see the best results when I’m doing low-impact mat workouts and Pilates. Whenever we try each other’s preferred method of training, it never works—and I’ve always wondered why. We are sisters, after all. But now thanks to a new study, it’s clear that when it comes to genetics and fitness, your DNA doesn’t matter as much as you think.

In a new study published in the Journal of Physiology, researchers used twins to assess whether or not preferred modalities of fitness were genetic. Over a six-month period, the 42 sets of twins—all of whom were perviously sedentary—did the same resistance and endurance training program. During the first three-month period, they ran or cycled. Then for the next three-month period, they lifted weights. All of their exercising was done together to ensure they were keeping their workouts as identical as possible.

At the end of each period, researchers measured two things: their aerobic capabilities and muscle strength. And even though the twins did the same exact program together for months, they didn’t always have the same results, showing the researchers genes don’t play as big of a role as previously thought. Even the identical twins had very different outcomes, which just goes to show that if a particular type of training works for someone else, it still might not be the best option for you—even if it’s someone you share DNA with.

If you’ve ever been discouraged because you’ve been doing the same virtual HIIT class as your bestie but she’s seeing crazy-good results while you don’t feel like you’re getting much out of it, switch things up. When you find the right program for you, your body will let you know.