Mayo Clinic: I am determined to get fit and lose weight this
year. Iíve recently heard a lot about interval training.
What is it exactly, and is it safe for everyone? How do I get
improve the fitness of your heart and lungs ó known as
cardiorespiratory fitness ó you need to exercise at a higher
level of intensity than is typical for you. High-intensity
aerobic interval training, also called HIIT, involves
alternating periods of moderate-intensity exercise with brief
periods of high-intensity exercise. Incorporating HIIT into
your exercise routine can be a safe and effective way to help
your body adapt to a more intense workout and become more fit.
are many benefits of HIIT, compared to moderate-intensity
exercise. For example, HIIT offers a more rapid and greater
increase in cardiovascular fitness. Itís also a time-saver.
The duration of exercise sessions may be shortened, since HIIT
exercisers expend the same or even greater number of calories
per session. In addition, people often find HIIT more
interesting and engaging than moderate-intensity exercise.
HIIT, you need to be able to tell the difference between
moderate-intensity exercise and high-intensity exercise. An
easy way to distinguish between the two is with the talk test.
During moderate-intensity exercise, you can talk, but you
cannot sing. During high-intensity exercise, you can only say
a few words before you need to take a breath. At
high-intensity, you feel physically challenged, and you can
only exercise for a limited time before you need to lower your
you begin HIIT, exercise at moderate intensity only for
several workout sessions until you can exercise continuously
at that level for at least 20 minutes. You can use whatever
form of aerobic exercise you prefer. Walking, jogging, biking
or working out on an exercise machine, such as an elliptical
trainer, are all good choices.
first time you use HIIT, warm up for five minutes at a
relatively easy pace. Then move to a moderate pace for about
five to 10 minutes. After that, switch to a high-intensity
pace for 30 seconds, then reduce your pace to back moderate
for one to three minutes to allow yourself to recover
completely. Repeat the high-intensity pace and
moderate-intensity recovery phases two or three times during a
30-minute exercise session.
are exercising at the higher intensity, you should be pushing
yourself, but you don't need to be working at your maximum
effort. During your exercise session, you should not
experience symptoms such as chest pain or discomfort, severe
shortness of breath or lightheadedness. If you do, stop
exercising right away. You also should not have unusual
fatigue, muscle pain or joint pain that lasts a long time
after you exercise. Talk to your health care provider about
any of these symptoms or about other symptoms you have during
exercise that seem out of the ordinary.
become accustomed to HIIT and your fitness improves, increase
the number of times you switch between high-intensity and
moderate-intensity to five or six per workout. You also can
increase the amount of time you stay at the high-intensity
pace to one to two minutes as you are able. Even as you become
more fit, include HIIT in only two or three of your exercise
sessions per week. Those sessions should not be on consecutive
be used effectively by athletes, as well as people of all ages
and fitness levels, including people with serious diseases,
such as coronary heart disease and chronic heart failure.
with your health care provider before you start HIIT,
especially if you have a chronic illness, such as heart
disease, lung disease, diabetes, high blood pressure, kidney
disease, stroke or arthritis.