In a 2015 New York Times interview, Dwayne "The Rock" Johnson said he knows how to make himself cry for emotional movie scenes. And it's not cutting onions.

Instead, it's listening to Whitney Houston's "Didn't We Almost Have It All."

In fact, reporter Melena Ryzik said Johnson's face "crumpled" when he mentioned the tune.

You, too, have experienced songs that can stir your emotions, making you happy (maybe "You Are the Sunshine of My Life" by Stevie Wonder) or riled up one way or another ("Something's Happening Here" by Crosby, Stills, Nash and Young, and perhaps "Versace on the Floor" by Bruno Mars).

Now researchers say that you can use that to your advantage when it comes to getting motivated to exercise.

For a new study in Psychology of Sport and Exercise, participants walked 400 meters on a track. Some listened to "Happy," by Pharrell Williams, some listened to a TED talk, and some had no soundtrack for the workout.

Those who listened to music were more alert and enjoyed the activity 38 percent more than those with no sound and 13 percent more than those listening to a podcast.

But if you're going to listen to music while you are exercising, do it safely.

Walking or jogging outdoors, stick to a track or trail where you don't need to cross streets or move through traffic.

If you are crossing streets or pedestrian traffic, drop the volume or remove headphones or earbuds. At home or the gym you can turn it up, but not so loud that you can't hear the smoke alarm.