If you want to rev up your fitness routine, consider high intensity interval training (HIIT). HIIT works by alternating short amount of high-intensity exercise followed by rest. The point is to build up lactic acid in the muscles, which boosts strength and stamina. HIIT is gaining ground in the fitness world because there are proven results in a short amount of time. Here are three benefits of the powerful workout:

1. Efficiency

No longer is the “too busy” excuse valid. Research shows that you can get in shape with just 15 minutes of interval training three times a week. Health experts say this form of exercise is much more efficient than jogging on a treadmill for an hour.

2. Do It Anywhere

Because HIIT doesn’t require equipment it can be done anywhere. Whether you are on a road trip or looking for a quick workout during a lunch break, all you need is shoes and somewhere to run.

3. Increase Metabolism

HIIT stimulates production of your human growth hormone (HGH) by up to 450 percent up to 24 hours after finishing your workout. HGH increases caloric burn and also slows down the aging process.