This Scientific Explanation Tells You How to Exercise More Efficiently

It was merely a decade ago when we began hearing about High-Intensity Interval Training (HIIT), making this a relatively new workout even for those with active lifestyles. 

Exercise physiologists have shown various studies on how intervals deliver the best results for the mind and the body, using evidence that shows improved endurance from alternating between sprints and jogging in a short period. As the years went on, popular workouts emerged, with the seven-minute workout routine in 2013 and the one-minute workout routine in 2016. 

Beyond the hype, let’s get down to the core of HIIT, its proven benefits, and why it’s about strength and conditioning rather than weight loss.

What is HIIT?

HIIT programs alternate between bursts of intensive activity and rest intervals or lower-intensity exercises. These workouts nowadays frequently include aerobic and strength training.

Most studies have concentrated primarily on aerobic exercise. As a result, the scientific knowledge of interval training is based on a more particular regimen than what is commonly done in gyms, exercise videos, and the media. The researchers’ definition is essential because when discussing evidence, we need to be precise about the types of exercises on which science is founded.

When addressing HIIT, experts refer to high-intensity exercises that push a person’s heart rate to 80% of its maximum capacity for one to five minutes, followed by periods of rest or less strenuous activity. 

According to Todd Astorino, a California State University San Marcos professor, “there is a strict definition of HIIT in terms of heart rate.” Although knowing when you’ve achieved an 80% heart rate is difficult, fitness trackers can help. SIT studies also include all-out bursts of intensity that require exceeding 100% of your heart’s capability.

Let’s Paint a Picture: HIIT in Action 

HIIT routines are almost unimaginable for anyone, and we never really know how they look until we perform them. In simple terms, HIIT is all about high-intensity bursts of activity. 

The lab-tested 4-by-4 workout from Norway, for example, includes a warmup, four four-minute periods, each with a three-minute recovery time, and is concluded by a cool-down. 

Thankfully, you can try something similar: Warm up with a 10-minute jog, then perform four four-minute intervals of faster running with three three-minute intervals of brisk walking in between, followed by a five-minute cooldown. You can also replace running with another cardio workout like swimming. The entire procedure should take no more than 40 minutes.

The Benefits of HIIT

One well-known advantage of HIIT is its potential to improve cardiorespiratory fitness while also saving time. No, it’s not about gaining muscle or burning fat—it’s about increasing the amount of endurance and the volume of oxygen the body can utilize.

In the 2016 SIT research, one group worked out for 10 minutes at various intervals, while the other worked out for 50 minutes at a constant tempo. What was the end result? Despite their different time demands, both groups improved their VO2 max. Since then, it has been determined that interval routines result in higher increases in VO2 max in a shorter amount of time than other kinds of training.

The case is simple: The human body reaps more benefits with quick high-intensity interval training than less intense programs that require more time.

HIIT for Weight Loss

HIIT promotes itself as a quick way to burn calories. Here, you’ll discover that 20-minute HIIT exercises may help you burn just as many calories as steady 50-minute routines. From a more scientific perspective, HIIT creates a more considerable disruption of the body’s homeostasis, which requires more energy and oxygen to return your body to normal basal levels.

Calorie burn in HIIT does not necessarily result in weight reduction. Despite popular belief, a 2019 study shows that HIIT and SIT produced almost the same results in terms of fat reduction. In addition to this, weight loss also involves looking deep into diet changes and opting for healthier food choices.


Amidst our busy lives, we must still see the importance of incorporating fitness into our daily and weekly routines. Although, we often face the challenge of crunched hours due to work, traffic, and other factors. Fortunately, HIIT’s fitness regimen allows us to get the most out of a high-intensity exercise in the least amount of time possible. 

Are you looking for a personalized fitness program in Wellesley? If you’re ready to make a healthy lifestyle change, The Fit Factor offers results-driven personal training that is sure to meet your fitness goals. Our programs are designed to give you precise one-on-one service to improve your nutrition, weight management, and holistic health. Get started today with our complimentary consultation!

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