HIIT [1] (high-intensity interval training) workouts have gotten a lot of attention lately because they're one of the best workouts for losing weight [2] and shedding belly fat. A HIIT workout mixes shorts bursts of activity with even shorter rest periods.

Here's a very basic HIIT running workout that can be done outside or on a treadmill.

The Workout

Directions: Begin with a five-minute warmup [3], then start running at an easy pace for two minutes. Then follow this format:

4 minutes: run fast (no need to sprint, but you should be huffing and puffing)
2 minutes: run at an easy recovery pace (or walk)

Repeat five times for a total of 30 minutes.

That's it! For more of a challenge, if you're on a treadmill, you can incorporate incline during those high-intensity intervals. After cooling down, do this postrun stretching routine [4].