Everyone knows that they should exercise. Research has clearly shown that exercise helps us live longer, happier, healthier lives. Aerobic exercise is one of the most common ways for people to get more active, but not all aerobic exercise is the same. High-intensity Interval training has completely transformed the world of sport because it is so much better than regular exercise. Here we will explain this technique and why it is so good for the body.

Walking is just the beginning.

Let’s begin by saying something that many people don’t want to hear: walking does not really count as exercise. Walking is certainly a good start, and it is definitely good for you. I encourage all my patients to walk as often as possible. To take the stairs, to choose the furthest parking spot they can and even consider getting a dog to get them walking every day.

People who walk regularly are healthier than people who don’t. But walking doesn’t usually make you break a sweat; it doesn’t make you short of breath or get your heart racing. In short, it doesn’t place your body under stress.

Exercise and Stress

Many people try to incorporate some kind of regular aerobic exercise into our lives, and there are many ways to do it. Your local gym likely has a huge amount of space dedicated to rows and rows of treadmills, stationary bikes, elliptical trainers, rowing machines or some other machine. These are designed to get your heart racing, your lungs pumping and your blood flowing in an effort to deliver oxygen to the tissues in your fast-moving limbs.

Exercise is good for you because it is hard – it stresses the body. This may sound confusing, because most of what is written about stress tells us that stress is dangerous and we should avoid it. It is absolutely true that stress can be dangerous, but not all stress is bad.

Good stress and Bad stress

One example of bad stress is psychological stress caused by worry, anger, constant thinking and lack of sleep. Whether it is personal or job-related, this kind of stress is dangerous. It makes our bodies release hormones and other chemicals that do bad things to the heart, the mind, the blood vessels and many other parts of the body.

That kind of damage is not just caused by psychological stress; it has also been linked to air pollution, tobacco and other environmental toxins, to a diet that is high in fat, refined sugars, food additives and preservatives.

Exercise is a completely different kind of stress. It is brief and much more intense, and is usually followed by a period of rest. This is the kind of stress that the body likes. It is the kind of stress it has been coping with for one million years of evolution – the kind of stress it needs. The short burst of stress that brief, intense exercise puts on your body stimulates a powerful healing response.

This is one of the main reasons that exercise is good for you. Whether you run, cycle, row, ski or swim, when your body is forced to work harder than it is used to, something different happens. The extra demand placed on your muscles, your heart, your lungs and even your mind is a stress, and the body’s response to that stress is very, very good for you.

High-intensity Interval Training

This is the basis for the best kind of aerobic exercise there is. It is called high-intensity interval training, and it has revolutionized the world of sports training and athletic performance. The goal is to subject the body to several bursts of stress that are more brief and more intense. Research comparing it to conventional exercise has confirmed what trainers and athletes have known for years – that interval training is better. It leads to a much more powerful healing response which works wonders for the body.

As an example, let us consider thirty minutes spent running outside or on a treadmill. The average runner would choose a pace that is challenging but not too difficult and simply runs at that pace for thirty minutes. A brief warm-up and a cool-down would be added before and after the run, but the rest of it would be at a fairly constant pace.

High-intensity interval training takes a completely different approach. Here, the runner would divide these thirty minutes into six groups of five minutes. Four to four and a half minutes would be spent walking or running at a very slow pace that is not difficult at all. This would be followed by 30-60 seconds of running at peak speed – as fast and hard as possible.

The short burst of 30-60 seconds of intense stress is all the body needs to trigger a healing response. Six of these five-minute cycles in a row results in six bursts of stress – each of which triggers its own healing response.

This has a much more powerful effect on the body than thirty minutes spent running at a steady pace. Instead of a steady level of stress that the body can quickly get used to, the bursts of activity force it to respond quickly again and again. This triggers a much more powerful healing response because it is more intense – and that healing response happens six times. As an aside, the interval training approach was popularized by a Canadian trainer at York University named Tudor Bompa.

Win-win

High-intensity interval training isn’t just more stimulating for the body - the brain likes it too. People who get bored or annoyed by regular aerobic exercise absolutely love it. Although you only spend a few minutes doing hard exercise, you feel like you have done much more. You look forward to the thrill of the challenge and you savour every moment of the rest, readying yourself for the next run. The highs and lows are a great change from the steady drone of a long run.

All living things have a miraculous ability to heal – to repair damage. Exercise is a powerful way to stimulate this healing response. Hundreds of research studies have proven that exercise is good for nearly every health problem – from depression and heart disease, to Alzheimer’s dementia and cancer. High-intensity interval training generates a much more powerful healing benefits of exercise. It is one of the best ways to get the benefits of exercise.

Note: Be careful with this approach if you suffer from angina, have not exercised for many years or have a very poor level of fitness. Stop immediately if you develop chest pain.