Dear A Moment of Science,

I've read that stretching before jogging or doing other exercise doesn't help prevent injury. If that's true, is there any reason to stretch at all?

Why Stretch?

It is true that stretching itself doesn't prevent injury while running or playing sports. But according to one study, stretching can raise your risk for injury if you're used to doing it and then stop. The same goes if you normally don't stretch before physical activity and then start.

Why Would Stopping Or Starting Stretching Make A Difference?

It's not entirely clear. But think about it this way: When you stretch your legs, say, you're loosening your tendons. And loose tendons can mean that when you're jogging, your feet stay in contact with the ground longer because the tendons are less springy.

So if you normally don't stretch and are used to jogging with tight, springy tendons, and then suddenly start stretching and end up jogging with loose tendons, that could slightly change your stride.

Be Careful When Exercising

The study mentioned only speculates on that point. The takeaway, though, is that it's not a good idea to abruptly change your exercise routine.

If you're used to stretching, either stay with it or gradually phase it out. And if you don't stretch before exercising, there's not much reason to start.

Read More:

• Stretch Before Running? New Twist on Old Debate (KATC)