Running, rowing, cycling, skipping: They may not just strengthen your heart, they may also actually repair it when it’s damaged.

Proteins that help keep cells healthy usually mend themselves when they get degraded from normal wear and tear. Sometimes, though, as in heart failure, damaged proteins accumulate and cause heart disease—and there’s no drug that can restore these essential cells to their previous grandeur.

But here’s where aerobic exercise—which we already know strengthens lungs, lowers cholesterol, reduces blood pressure, and improves the immune system—comes in.

New research on rats found that when rodents with damaged hearts were put on a steady routine of intense cardiovascular exercise (no doubt wearing tiny little leg warmers and sweating to a Jane Fonda’s Workout tape), their cardiac proteins were restored, making their broken tickers healthy again, the Journal of Cellular and Molecular Medicine reports.

It’s an amazing discovery, because it shows just how powerful exercise—specifically, aerobic exercise—is at boosting heart health. And though the findings will be most immediately beneficial to people already dealing with heart failure, they also reinforce how important working out is to our cardiovascular system.

So get in at least 25 minutes of vigorous aerobic activity three days a week (the American Heart Association’s recommendation) and add at least two days a week of resistance exercise to keep that pump primed.

BY ADAM BIBLE