Being flexible can actually help you live longer, scientists say. Here's why.

• Being more flexible is linked to a lower risk of dying early, new evidence suggests.
• Incorporating more flexibility exercise may boost longevity in older adults, a researcher said.
• Previous studies show flexibility exercise like yoga and tai chi have other health benefits too.

Longevity is one of the hottest trends in fitness, and new research points to key metric to watch if you're working out for a longer life.

Flexibility, measured by how well your joints move through a range of motion, is linked to a lower risk of dying early, according to a study published August 21 in Scandinavian Journal of Medicine & Science in Sports.

Researchers from more than half a dozen clinics and universities around the world, including Stanford, analyzed data from 3,139 men and women, aged 46 to 65 years old. They assessed participants' flexibility, based on a range of motion through the ankles, hips, knees, shoulders, torso, wrists, and elbows. The researchers then compared that score with participants' risk of dying over an average of almost 13 years of follow up.

The results suggests that people with a higher flexibility score were significantly less likely to die during the study than participants with a lower score.

Women were 35% more flexible, on average, than men, according to this study (and tend to live longer, too, per CDC data).

A caveat is that this study was observational, meaning more research is needed to see if improving flexibility can help people live longer.

Still, researchers say this tracks. We already know that cardio, strength training, and other types of exercise can help extend lifespan. "Being aerobically fit and strong and having good balance have been previously associated with low mortality. We were able to show that reduced body flexibility is also related to poor survival in middle-aged men and women," Araújo said in a press release.

The best exercises to improve flexibility

More research could also help determine which exercises are best for improving flexibility, and longevity. There's already promising evidence that flexibility-boosting workouts like tai chi and yoga can be good for overall health, too.

For now, findings suggest that doing flexibility exercises as we get older could be beneficial, according to Dr. Claudio Gil S. Araújo, lead author of the study and doctor at the Exercise Medicine Clinic Clinimex in Rio de Janeiro.

Exercises like a runner's lunge or 90/90 stretch are great for building flexibility. You can also try yoga.

Don't forget mobility, too

Mobility, which is similar to flexibility, can also improve your chances not only of living a long life, but being able to stay active and healthy for longer, trainers previously told Business Insider.

That's all the more reason to have a well-rounded workout routine that includes working in a full range of motion, with movements like deep squats, to improve mobility.