Did you know that a short burst of intense exercise is extremely beneficial not only for overall fitness, but for building lean muscle tissue and promoting longevity?
Just imagine exercising from only two minutes to a maximum of 17 a couple of times a week and still reaping the benefits of cardiovascular fitness. With lack of time one of the major reasons most people can't make a commitment to regular exercise, very short, intense bouts of exercise present a solution—and with more benefits than longer workouts.
According to a study published in the Journal of Applied Physiology (April, 2005), 23 men and women aged between 25 and 35 were tested to see how long it took them to cycle 18.6 miles. They all did some form of regular exercise, and were then given varying exercise programs three times a week as part of the study to see which one was the most effective for overall fitness.
The first group cycled for two hours a day at a moderate pace. The second group rode harder for 10 minutes a day in 60-second bursts. The last group cycled at an intense sprint for two minutes in 30-second bursts, with four minutes of rest in between each sprint.
At the end of the two weeks, each of the three groups was asked to repeat the 18.6 mile cycling test. Every subject was found to have improved to the same degree. Further tests showed that the rate at which the subjects' muscles were able to absorb oxygen also improved to the same level.
What this study showed is that in terms of overall health and fitness, the group that did just the two-minute workout showed the same muscle fitness results. In addition, this group also showed improved muscle enzymes, which are essential for the prevention of Type 2 diabetes. Yet the most interesting correlation was that this group showed the same benefits of cardiovascular fitness as did the group who exercised for 10 times as long (20 minutes). That is a huge bonus in the face of growing levels of unfitness and obesity, which is becoming an epidemic in Australia, the U.S. and the U.K.
The author of the study, Prof. Martin Gibala of the Health Department of McMaster University in Ontario, said: "We thought there would be benefits, but we did not expect them to be this obvious. It shows how effective short, intense exercise can be."
An article published in the UK Telegraph, "6 Minutes of Exercise A Week As Good As 6 Hours" by Peter Zimonjic elaborates on this study. "Just six minutes of intense exercise a week does as much to improve a person's fitness as a regime of six hours," writes Zimonjic. "Moderately healthy men and women could cut their workouts from two hours a day, three times a week, to just two minutes a day and still achieve the same results, claim medical researchers."
What the study also proved is that a person can get the same level of fitness and in a much shorter period if she or he is willing to endure a high-intensity activity for a short burst only. In practice, this would be like three to five short, intense bursts of running uphill, cycling, stepping on a stem machine, or biking, and then resting for up to two minutes in between each of the intense sets.
Running or jogging for 25 minutes or more is not for everybody. The idea of doing a short burst of intense exercise might appeal to people who don't have much time to exercise.
Another benefit of a short burst of intense exercise is that it does not push the body into stress mode. Exercise is a form of stress. In the right measure it is a healthy stress, as it engages the body in adaption to stress which leads to fitness. But too much physical stress is counterproductive as the adrenal glands start to produce too much stress hormone mainly cortisol, which literally eats away existing muscle tissue and makes the body store fat for energy.
According to Dr Alan Sears, who developed PACE (Progressively Accelerating Cardiopulmonary Exertion) training after decades working with obese patients, the problem with long-duration exercise or aerobic exercise is that it can actually encourage your body to store fat under certain circumstances. Additionally, if you aren't careful, you can shrink your heart and lungs, increasing your risk of heart attack.
Here's how Dr. Sears explains it: "Long-duration exercise isn't natural. Our ancient ancestors never ran for mile after mile without rest or recovery. Their exercise was primarily hunting with short bursts of exertion, followed by periods of rest." By exercising in short bursts, followed by periods of recovery, you recreate exactly what your body needs for building fitness.
According to Dr. Sears, the problem of doing long sessions of aerobics and/or jogging is that, once you pass the 15-to-20-minute mark of continuous exercise, your body is burning fat as fuel. While this may sound great in principle, in actuality it is not ideal for optimal fitness or long term fat loss. Here's why: aerobics or continuous exercise for over 15 or 20 minutes signals your body to burn fat and, as a result, it will make and store more fat in preparation for its next workout. This becomes a cycle, making it very difficult to lose that stubborn fat the body thinks it needs.
When you exercise for no more than 20 minutes at one time and your regime consists of any form of exercise—such as stationary bike, cycling or running up a small hill, even doing 50 start jumps for up to a minute followed by rest/recovery for up to two minutes—you are doing what Dr Sears calls supra-aerobics, beyond aerobics. That is training your body to recover quickly and build lean muscle tissue in preparation for its next intense training session. This is really a modified version of interval training.
Either way, when you are doing interval or PACE training exercise only for short bursts followed by rest and recovery, as opposed to continuous endurance training, your body is forced to burn carbohydrates (in the form of glycogen stored in the muscles and liver during your exercise) instead of fat. This is a biological loop that has many great benefits.
Why is a short burst of exercise so beneficial?
Because after you finish your PACE or interval training routine, your body starts burning fat to replace the lost glycogen from your muscles/liver that it has just used up during your training —and, it will continue to do so for 24 hours. After a few weeks, your body gets the message that it doesn't need to store spare fat because it is not burning fat as fuel during exercise, and that it needs lean muscle tissue instead of fat for the intense workouts.
The other great benefit of doing PACE is that you only need to do it three or four times a week, not every day, because of that 24-hour fat-burning effect after your intense workouts.
Carl Lewis, the winner of nine Olympic gold medals, credits interval training for his record-breaking career. He even recommends it to non-athletes who want to reach their highest potential.
The benefits of PACE training are supported by the Harvard Health Professionals Study. That study, published by the researchers after studying over 7,000 people, found that the key to preventing heart disease is intensity, not long-duration exercise. In another Harvard study, intensity turned out to be the key to longevity and reduced risk of death because it forces your lungs and heart to expand, adapt and recover from stress quickly.
In summary, we could all benefit from regular exercise, because our bodies are designed to move. We need to engage in some form of physical activity in order to cope better with daily stress. Physical exercise trains our bodies to adapt to stress. Yet if we exercise too much or for too long, it can become counterproductive and lead to overtraining.
Overtraining catabolizes or literally eats away existing muscle tissue and prevents your body from fully recovering, as well as from building more lean muscle tissue. Any form of exercise that promotes lean muscle tissue is beneficial, as having more lean muscle tissue promotes strength, vitality and a faster metabolism. Short, intense bursts of exercise have proven to build more lean muscle than aerobic/endurance workouts lasting for more than 25 minutes.
The wonderful thing about doing PACE or short, intense training is that it is exhilarating. It takes your mind off other things at that moment of intensity. The short burst of intensity releases adrenaline and endorphins, all of which create a feeling of aliveness. Surely that's exercise worth doing, and relatively easy to include in our regular routine three or four times a week."
Teya Skae is a Sydney, Australia-based clinical kinesiologist, nutritionist, health coach and the founder of the website Empowered Living.