Are you ready to shake up your workout? Do you wish you could burn more calories without spending more time at the gym? Consider aerobic interval training, sometimes called high-intensity interval training (HIIT). Once the domain of elite athletes, interval training has become a powerful tool for the average exerciser, too.
What is interval training?
It's not as complicated as you might think. Interval training is simply alternating short bursts (about 30 seconds) of intense activity with longer intervals (about 1 to 2 minutes) of less intense activity.
For instance, if your exercise is walking and you're in good shape, you might add short bursts of jogging into your regular brisk walks. If you're less fit, you might alternate leisurely walking with periods of faster walking. For example, if you're walking outdoors, you could walk faster between certain mailboxes, trees or other landmarks.
What can interval training do for me?
Whether you're a novice exerciser or you've been exercising for years, interval training can help you make your workout routine more exciting. Consider the benefits:
- You'll burn more calories. The more vigorously you exercise, the more calories you'll burn — even if you increase intensity for just a few minutes at a time.
You'll be more time efficient. Many people don't exercise because they say they don't have time. The Department of Health and Human Services recommends 150 minutes of moderate aerobic activity or 75 minutes of vigorous aerobic activity a week, or a combination of moderate and vigorous activity.
Interval training enables you to complete an effective workout in less time than a standard cardiovascular workout. For example, you might complete a workout in about 15 to 20 minutes or less instead of 40 minutes.
You'll improve your aerobic capacity. As your cardiovascular fitness improves, you'll be able to exercise longer or with more intensity. Imagine finishing your 60-minute walk in 45 minutes — or the additional calories you'll burn by keeping up the pace for the full 60 minutes.
Improving your cardiovascular fitness can also help reduce your risk of heart disease, high blood pressure and diabetes.
- You'll keep boredom at bay. Turning up your intensity in short intervals can add variety to your exercise routine.
- You don't need special equipment. You can perform intervals walking, running, biking or swimming. Or you can work out on an elliptical trainer, treadmill or exercise bike. Interval training can also include body-weight exercises, such as jumping jacks, squats and lunges.
Are the principles of interval training the same for everyone?
Yes — but you can take interval training to many levels. If you simply want to vary your exercise routine, you can determine the length and speed of each high-intensity interval based on how you feel that day.
After warming up for a few minutes, you might increase the intensity for 30 seconds and then resume your normal pace. Finish with a cool-down. How much you pick up the pace, how often and for how long is up to you.
If you're working toward a specific fitness goal, you may want to take a more scientific approach. A personal trainer or other expert can help you time the intensity and duration of your intervals — which may include movement patterns similar to those you'll use during your sport or activity. The trainer may time the intervals based on factors such as your target heart rate and the ability of your heart and lungs to deliver oxygen to your muscles (peak oxygen intake).
Does interval training have risks?
Interval training isn't appropriate for everyone. If you have a chronic health condition or haven't been exercising regularly, consult your doctor before trying any type of interval training.
But it may be appropriate for people who are older, less active or overweight. Studies suggest that interval training can be safe and beneficial even in people with heart disease and type 2 diabetes.
Also keep the risk of overuse injury in mind. If you rush into a strenuous workout before your body is ready, you may injure your muscles, tendons or bones. Interval training doesn't have to involve high-impact exercise, ballistic or jumping movements, or heavy weights.
Instead, start slowly. Try doing just one or two higher intensity intervals during each workout at first. If you think you're overdoing it, slow down. As your stamina improves, challenge yourself to vary the pace. You may be surprised by the results.