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How It Works

As you can tell from the name, high-intensity interval training (HIIT) is challenging. It takes your cardioworkout to another level, as you push your pace out of your comfort zone.

You can use HIIT with any type of cardio workout, whether it's running, using a stair climbing machine, rowing, or jumping rope.

You’ll work up a sweat fast, working at a very intense level and then backing off for a slower recovery period, followed by another round of high intensity.

That strategy can save you time: You don't have to work out as long as you would if you were keeping a steady pace.

You’ll lose weight, build muscle, and boost your metabolism. Plus there’s a post-workout bonus: Your body will burn calories for about 2 hours after you exercise.

Intensity Level: High

You’ll work harder than you do when you do a typical cardio workout. But you’ll do it in spurts of 30 seconds to 3 minutes. Then you’ll have a chance to recover for about the same amount of time or longer.

Areas It Targets

Core: No. This workout doesn’t target your core.

Arms: No. This workout doesn't target your arms.

Legs: No. This workout doesn’t target your legs. But cardio exercises like running and biking can strengthen your legs.

Glutes: No. This workout doesn't target your glutes. But if you do cardio exercises that work your glutes, like stair-climbing, your glutes will get a workout.

Back: No. This workout doesn't target your back.


Flexibility: No. This workout doesn’t focus on improving flexibility.

Aerobic: Yes. This is a powerful cardio workout.

Strength: Yes. This workout can help you build muscle. Choose weight lifting as your high-intensity activity for an extra boost in strength.

Sport: No.

Low-Impact: No. But if you work out on an elliptical trainer, it may be low-impact.

What Else Should I Know?

Cost: Free.

Good for beginners? Yes. You can start with just 3-4 speed intervals, then ramp it up as you get better.

Outdoors: Yes. Run or bike outdoors. You can even try chasing your dog for each speed interval.

At home: Yes. This is a great workout to use on the treadmill or stationary bike. Or you can do weight-lifting intervals at home.

Equipment required? None, unless you plan to work out on cardio equipment like a treadmill or stair-climbing machine, or with a weight set.

What Physical Therapist Ross Brakeville Says:

If you exercise regularly, HITT is a great alternative to your routine. Plus, this high intensity workout really gets the feel-good endorphins flowing.

HITT is not for everyone. You need great motivation and physical stamina to push yourself to the limit. If you’re not used to this type of training, your muscles and joints may pay the price through sprains and strains.

Is It Good for Me If I Have a Health Condition?

Getting and staying fit is part of managing conditions like diabetes, high blood pressure, high cholesterol, or heart disease. And HIIT is a great way to lose weight and boost your overall health.

This workout places big demands on your heart, so you should check in with your doctor see if HIIT is OK for you. You should also start slowly, doing a few intervals for a short period of time.

You may not be able to do HIIT if you have joint or muscle problems, like arthritis. Ask your doctor first.

If you're pregnant, you did HITT before pregnancy, and you don’t have any other medical issues, then it should still be a safe option for you during your first trimester.

In the second and third trimesters, your growing belly is going to limit your activity. You should only do high-impact training if you have your doctor’s approval. Make sure you drink plenty of water and don’t overheat.

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