There are plenty of reasons to practice regular exercise, but in case you’re still not convinced, scientists at the University of Waterloo in Canada have discovered one more: ocular health.

The new study focuses on what’s known as tear film, the protective layer that stops dust, dirt, and other irritants from getting to your eyeballs. Every time we blink, a fresh coating of the tear film is layered over the eye, which is critical in preventing itchiness, stinging, dry eyes, and infection.

“With so much of our activity tied to screen usage, dry eye symptoms are becoming increasingly common,” explains Heinz Otchere, a Ph.D. candidate in vision science at the University of Waterloo. “Instead of having to use eye drops or other alternative treatments, our study aimed to determine if remaining physically active can be an effective preventative measure against dryness.”

The scientists divided 52 participants into an “athlete” or “non-athlete” group, with the athletes exercising at least five times a week, and the on-athlete group a maximum of one. Then, each participant underwent visual assessments of their eyes both before and five minutes after each session.

All participants’ formation and stability of tear films showed improvement following every exercise session, however, each individual’s physical fitness and the duration of each session impacted the level of improvement. The studies showed that the “athlete” group was found to have a “much appreciable improvement” compared to the “non-athlete” group.

“It can be challenging for people to regularly exercise when the demand is there to work increasingly longer hours in front of screens,” says Otchere. “However, our findings show physical activity can be really important for not just our overall well-being, but for our ocular health too.”

Source study: Experimental Eye Research – Differential effect of maximal incremental treadmill exercise on tear secretion and tear film stability in athletes and non-athletes