To live a healthy life there are many things to consider and the first of these, in my opinion, is a healthy nutrition plan that encourages lots of nutrient-dense food.
But our overall health is not determined by any one thing; it is multi-factorial.
Once we have our nutrition plan optimized, we should look at other lifestyle factors that can influence our health.
Exercise is one of these other major considerations and in this article, I’ll introduce one of the best forms of it: high-intensity interval training.
What is High-Intensity Interval Training?
High-intensity interval training, otherwise known as HIIT, is a form of training where you exercise intensely in short bursts.
Instead of sustained, steady-state exercise, the key is to give 100% effort for a short duration. Following this, a rest period can be taken to recover.
This routine of intense effort followed by a small rest repeats for the duration of the workout.
High-intensity interval training can take many different forms. One example of how to do it is sprints. Sprint for 30 seconds, and then take a rest, and then sprint again for another 30 seconds. Repeat this ten times and you can finish – just a ten-minute workout.
Why should we consider this type of exercise?
Because the impacts on our overall health are so impressive.
Below I have listed some amazing health benefits of high-intensity interval training, all backed by science.
High-Intensity Interval Training Burns More Fat
Go to any local gym and what do you see? If it’s anything like the gyms I’ve been to, then you’ll see lots of people moving slowly on a treadmill while watching TV. We can call this type of exercise ‘steady state’.
Intense exercise at a higher VO2 max increases the rate of fat oxidation, meaning that more calories are burned by HIIT when compared to standard low-intensity workouts. This includes during the actual workout, and for some time afterward too.
Why walk on a treadmill for hours when you can burn more fat in less than ten minutes?
But don’t just take my word for it…
HIIT vs. Steady State Exercise: What Does the Science Say?
A study that directly compared HIIT to steady state exercise found that while both types of exercise improve cardiovascular health, only HIIT was associated with significant reductions in total body fat, subcutaneous trunk and leg fat, and insulin resistance (1).
Furthermore, in a trial involving sixteen middle-aged men with type 2 diabetes, the introduction of an HIIT program resulted in an average 44% decrease in abdominal fat over eight weeks (2).
And there’s more: the graph below summarizes a range of studies. We can see that HIIT has significant impacts on reducing body fat (3).
All exercise is good for you. But HIIT is much better for losing fat.
High-Intensity Interval Training Protects Your Heart
Many people exercise because they want to improve their cardiovascular health.
That doesn’t mean you have to go running for hours every week, though. In fact, high-intensity interval training is associated with many cardio-protective benefits.
A 2015 study reported on a 74-year-old man with atrial fibrillation. He was put on a 10-week high-intensity interval training program that resulted in significant improvements in heart rate, blood pressure, aerobic and functional capacity, and quality of life (4).
It’s great to see anecdotes like this, and it helps destroy the myth that older people should avoid intense exercise. When we give up exercise, we age faster, lose muscle and bone mass, and overall health declines (5, 6, 7).
Another study showed that high-intensity interval training increases metabolites of nitric oxide, which may protect against cardiac injuries (8).
Widely considered the “gold standard” for a study, a randomized controlled trial investigated the effect of a 6-week high-intensity interval training protocol in obese or overweight men. The results showed improved insulin sensitivity, reduced blood lipids, decreased body fat, and improved cardiovascular fitness across the board (9).
Exercise is important.
A combination of resistance training, frequent movement, and occasional high-intensity interval training can have a great deal of benefits on our health.
And this is true whether someone is in their twenties or their seventies.
You are never too old for exercise.
High-intensity interval training improves cardiovascular health.
High-Intensity Interval Training Needs No Equipment
You can do HIIT anywhere.
It requires no equipment, meaning you don’t need an expensive gym membership.
Live in the city? Go to a park. Live near the sea? Even better – do some sprints on the beach.
This level of accessibility is probably the best advantage of HIIT – anyone can do it, and they can do it anywhere.
It may not seem like a health benefit – but it is. In a study featuring 2236 participants, over 55% cited “lack of time” as their biggest barrier to exercise (10).
Remove the time burden of physical activity and you remove the most significant obstacle.
Dr. Ted Naiman is a big proponent of HIIT and, for inspiration, I suggest you check out some of his great ideas on exercises to incorporate.
High-intensity interval training is FREE and doesn’t need a gym membership.
High-Intensity Interval Training Improves Health Markers
An excellent benefit of HIIT is that it improves your overall health in a short period.
Research looking into the effect of HIIT on health markers confirms this.
HIIT protocols significantly improve insulin sensitivity in young men. One study showed that after only two weeks of high-intensity interval training, insulin sensitivity had improved by 23% (11).
A study (in mice) also found that HIIT decreases blood-glucose levels by improving adipose and liver insulin sensitivity (12).
Analyzing the physiological response of an HIIT workout, one study noted increased blood glycerol levels and free fatty acids, suggesting triglycerides had been broken down (13).
High-Intensity Interval Training Has Benefits for Heart Disease
Some more good news: HIIT improves health in patients with a variety of medical conditions.
In an obese study group, twice-weekly HIIT sessions improved the known cardiovascular risk factors (14).
Research comparing the impact of HIIT with moderate intensity exercise found that high-intensity interval training is superior for increasing aerobic capacity in patients with coronary heart disease (15, 16).
Note: If you have any medical condition, then you should always discuss with your doctor before starting any exercise program.
HIIT significantly improves health markers – in both healthy and sick groups.
HIIT Helps Preserve Muscle
For dieters and especially athletes, preservation of muscle is important when trying to lose weight. We want to lose fat, not just overall weight.
Fortunately, another great benefit of HIIT is that research suggests it is far greater for muscle preservation than lower intensity forms of exercise.
One study compared participants split into two forms of exercise program. One group exercised at 45% of VO2 max, while the other group exercised at 72%. Both groups of participants lost significant amounts of fat. However, the low-intensity exercise group lost more overall weight. The reason? The higher-intensity group preserved more muscle mass (17).
Burn fat – not muscle.
HIIT preserves muscle mass better than lower intensity exercise.
High-intensity interval training is something to consider whether you are looking to lose fat, increase athletic performance, or just improve your overall health.
Many of us follow a nutrition protocol that improves health markers such as blood-glucose level and insulin sensitivity, and yet HIIT also helps provide these same benefits.
Nutrition is a crucial part of our overall health, but if we want optimal health, then we should also implement beneficial forms of exercise.
And high-intensity interval training is one of the very best possible choices.