7 Benefits of High-Intensity Interval Training
7 Benefits of High-Intensity Interval Training (HIIT)
While most people know that physical activity is healthy, it’s estimated that about 30% of people worldwide don’t get enough (1Trusted Source).
Unless you have a physically demanding job, a dedicated fitness routine is likely your best bet for getting active.
If this sounds like you, maybe it’s time to try high-intensity interval training (HIIT).
HIIT is a broad term for workouts that involve short periods of intense exercise alternated with recovery periods.
One of the biggest advantages of HIIT is that you can get maximal health benefits in minimal time.
This article explains what HIIT is and examines 7 of its top health benefits.
What Is High-Intensity Interval Training?
Typically, a HIIT workout will range from 10 to 30 minutes in duration.
The actual activity being performed varies but can include sprinting, biking, jump rope or other body weight exercises.
For example, a HIIT workout using a stationary exercise bike could consist of 30 seconds of cycling as fast as possible against high resistance, followed by several minutes of slow, easy cycling with low resistance.
This would be considered one “round” or “repetition” of HIIT, and you would typically complete 4 to 6 repetitions in one workout.
The specific amount of time you exercise and recover will vary based on the activity you choose and how intensely you are exercising.
Regardless of how it is implemented, high-intensity intervals should involve short periods of vigorous exercise that make your heart rate speed up (8Trusted Source)
Not only does HIIT provide the benefits of longer-duration exercise in a much shorter amount of time — it may also provide some unique health benefits
1. HIIT Can Burn a Lot of Calories in a Short Amount of Time
One study compared the calories burned during 30 minutes each of HIIT, weight training, running and biking.
The researchers found that HIIT burned 25–30% more calories than the other forms of exercise (9Trusted Source).
In this study, a HIIT repetition consisted of 20 seconds of maximal effort, followed by 40 seconds of rest.
This means that the participants were actually only exercising for 1/3 of the time that the running and biking groups were.
Although each workout session was 30 minutes long in this study, it is common for HIIT workouts to be much shorter than traditional exercise sessions.
This is because HIIT allows you to burn about the same amount of calories, but spend less time exercising.
2. Your Metabolic Rate Is Higher for Hours After Exercise
One of the ways HIIT helps you burn calories actually comes after you are done exercising.
In the same study, HIIT was also found to shift the body’s metabolism toward using fat for energy rather than carbs.
Another study showed that just two minutes of HIIT in the form of sprints increased metabolism over 24 hours as much as 30 minutes of running (14Trusted Source).
3. It Can Help You Lose Fat
Studies have shown that HIIT can help you lose fat.
One review looked at 13 experiments and 424 overweight and obese adults.
Additionally, one study found that people performing HIIT three times per week for 20 minutes per session lost 4.4 pounds, or 2 kgs, of body fat in 12 weeks — without any dietary changes (16Trusted Source).
Perhaps more important was the 17% reduction in visceral fat, or the disease-promoting fat surrounding your internal organs.
4. You Might Gain Muscle Using HIIT
Additionally, it’s important to note that increases in muscle mass are more likely to occur in individuals who were less active to begin with (24Trusted Source).
Some research in active individuals has failed to show higher muscle mass after HIIT programs (25Trusted Source).
Weight training continues to be the “gold standard” form of exercise to increase muscle mass, but high-intensity intervals could support a small amount of muscle growth (24Trusted Source, 26Trusted Source).
5. HIIT Can Improve Oxygen Consumption
Oxygen consumption refers to your muscles’ ability to use oxygen, and endurance training is typically used to improve your oxygen consumption.
Traditionally, this consists of long sessions of continuous running or cycling at a steady rate.
One study found that five weeks of HIIT workouts performed four days per week for 20 minutes each session improved oxygen consumption by 9% (6Trusted Source).
This was almost identical to the improvement in oxygen consumption in the other group in the study, who cycled continuously for 40 minutes per day, four days per week.
Another study found that eight weeks of exercising on the stationary bike using traditional exercise or HIIT increased oxygen consumption by about 25% (7Trusted Source).
Once again, the total time exercising was much different between groups: 120 minutes per week for the traditional exercise versus only 60 minutes per week of HIIT.
6. It Can Reduce Heart Rate and Blood Pressure
HIIT may have important health benefits, as well.
In this study, the endurance training group exercised four days per week for 30 minutes per day, but the HIIT group only exercised three times per week for 20 minutes per day.
Some researchers have found that HIIT may even reduce blood pressure more than the frequently recommended moderate-intensity exercise (29Trusted Source).
However, it appears that high-intensity exercise does not typically change blood pressure in normal-weight individuals with normal blood pressure (20).
7. Blood Sugar Can Be Reduced by HIIT
Based on this information, it is possible that high-intensity exercise is particularly beneficial for those at risk for type 2 diabetes.
In fact, some experiments specifically in individuals with type 2 diabetes have demonstrated the effectiveness of HIIT for improving blood sugar (32Trusted Source).
How to Get Started With HIIT
There are many ways to add high-intensity intervals to your exercise routine, so it isn’t hard to get started.
To begin, you just need to choose your activity (running, biking, jumping, etc.).
Then, you can experiment with different durations of exercise and recovery, or how long you are performing intense exercise and how long you are recovering.
Here are a few simple examples of HIIT workouts:
- Using a stationary bike, pedal as hard and fast as possible for 30 seconds. Then, pedal at a slow, easy pace for two to four minutes. Repeat this pattern for 15 to 30 minutes.
- After jogging to warm up, sprint as fast as you can for 15 seconds. Then, walk or jog at a slow pace for one to two minutes. Repeat this pattern for 10 to 20 minutes.
- Perform squat jumps (video) as quickly as possible for 30 to 90 seconds. Then, stand or walk for 30 to 90 seconds. Repeat this pattern for 10 to 20 minutes.
While these examples can get you started, you should modify your own routine based on your own preferences.