Is High Intensity Interval Training (HIIT) the Best Type of Exercise?

Kathryn Adel September 3, 2018 sports

High Intensity Interval Training (HIIT), also known as short interval training, has been gaining popularity over the years. It consists of alternating between short periods of very intense physical effort with periods of recovery at a lower intensity. For example, the Tabata method (which includes repetitions of 20 seconds of intense effort followed by 10 seconds of rest) has become one of the most popular forms of HIIT training. This form of training is praised by its supporters for its potential to burn a lot of calories in a short period of time and for its effectiveness with weight loss. However, is this type of training the best choice for everyone? Let’s dive into the question further!

5 advantages of HIIT:

1. Improves cardiorespiratory fitness and athletic performance

HIIT training is effective in improving anaerobic capacity, which is important for sports that require short and intense efforts such as team and combat sports. HIIT can be even more effective when it is customized according to the sport, for example doing jump intervals for volleyball players or punching intervals on a heavy bag for boxers. Interval training (including HIIT) also increases VO2max and aerobic capacity and is, therefore, very useful for endurance athletes.

2. Effects on weight loss

HIIT training, thanks to its high intensity, burns more calories in less time than continuous training. In addition, it is accompanied by an increase in resting metabolism, which means that the energy expenditure is increased in the hours following a HIIT-type training compared to after a continuous lower intensity exercise. According to the results of two meta-analyzes, HIIT training is effective in promoting weight loss, including abdominal and visceral fat loss.

3. Effects on lowering the risk of chronic diseases

HIIT is an effective training method to reduce the risk of chronic diseases. A meta-analysis has shown that HIIT training can reduce blood pressure and fasting blood glucose levels in obese or overweight people. A recently published study found that with women, HIIT was as effective as continuous training in improving lipid profile and glycemic control, while allowing 25 to 56% less time spent on training per week.

4. Convenient for people in a hurry

A common reason people give for not doing physical activity is a lack of time. Since the intensity of a HIIT workout is very high, it cannot be sustained for a long period of time. The total duration of a HIIT session usually lasts for 15 to 30 minutes. Thus, this training method is useful for improving physical fitness while expending a lot of calories in a short period of time. But beware, even if condensing your physical activity seems a tempting solution, it is not a reason to become sedentary the rest of the time!

5. Requires little equipment

With the weight of your body and the right choice of exercises (such as jumping squats, jumping jacks, burpees, push-ups or even running intervals), you can easily get a very intense complete workout without equipment!

A good choice for some, but not for all!

A common perception is that HIIT training is just for people who are in excellent physical condition. On the contrary, it can be adapted according to the abilities of each, by varying the duration and intensity of the periods of physical effort, the recovery time, and the chosen sport (for example cycling versus running). However, due to its higher intensity, this type of training is associated with a higher risk of joint injuries and is not the best choice for people who have a greater susceptibility to injury. In addition, high intensity exercise causes a short-term increase in blood cortisol, which is the stress hormone. Thus, people who already have high metabolic stress parameters would benefit from following a more moderately intense workout. Finally, the benefits of continuous training and HIIT training on body composition and lowering risk factors for chronic diseases would seem to be quite similar, except that continuous training requires more time. In reality, the most effective training will most likely be the one that you will be able to perform on a regular basis and sustain over the long term. It is, therefore, up to you to choose whether you prefer continuous training, HIIT, or a combination of the two.

References

• Maillard et coll. (2018) Effect of High-Intensity Interval Training on Total, Abdominal and Visceral Fat Mass: A Meta-Analysis. Sports Med; 48(2):269-288.
• Wewege et coll. (2017) The effects of high-intensity interval training vs. moderate-intensity continuous training on body composition in overweight and obese adults: a systematic review and meta-analysis. Obes Rev; 18(6):635-646.
• Alvarez et coll. (2018) High-Intensity Interval Training as a Tool for Counteracting Dyslipidemia in Women. Int J Sports Med; 39(5):397-406.
• Batacan et coll. (2017) Effects of high-intensity interval training on cardiometabolic health: a systematic review and meta-analysis of intervention studies. Br J Sports Med; 51(6):494-503.

Author

Kathryn Adel

Kathryn holds a Bachelor Degree in Nutrition as well as a Bachelor and a Master Degree in Kinesiology, all from Laval University. She is a Registered Dietitian and active member of the Ordre professionnel des Diététistes Nutritionnistes du Québec (ODNQ) and of the American Academy of Nutrition and Dietetics. She holds the Monash University's certification for the FODMAP diet and IBS, and has considerable clinical experience in that area. She is also an accomplished athlete, having ran track and cross-country at a national level. Kathryn specializes in sports nutrition, weight loss, diabetes, as well as heart and gastrointestinal health.