Take a beating

How a vigorous workout can not only keep your heart in top shape, but also help reverse damage in a dysfunctional ticker.

Your heart loves a tough workout and now scientists have figured out why. Researchers from Norway put rats through their paces to investigate what happens inside the heart during high-intensity interval training (HIIT). They found that this type of exercise improves the way heart cells manage calcium (which initiates beating) and conduct electrical signals, allowing the heart to do its job more rhythmically and powerfully.

The best part? Even if your ticker is already showing signs of dysfunction in these areas, the scientists say regular exercise, especially

HIIT, can help reverse the damage.