What if there was a way that you could get the benefits of exercise without having to do the exercise? Many people are interested in finding such a shortcut to health and fitness. Some of these ideas are pretty creative. Take this one, for example: Exercise increases your heart rate and causes you to sweat. So does sitting in a sauna. But is sitting in a sauna a shortcut to getting the benefits of exercise? The answer is no!
It’s true that exercise causes your heart rate to increase and you sweat because your body temperature goes up, but these are responses to exercise, not benefits of exercise. The health and fitness benefits of exercise are due to adaptations that occur mainly in the muscle, heart and blood vessels. These adaptations include the heart becoming bigger and stronger, the blood vessels becoming more elastic and less stiff and the muscle changing to become more resistant to fatigue and better able to generate force.
The adaptations depend on the type of exercise, so lifting weights causes the muscle to grow larger, called hypertrophy, and stronger while endurance exercise such as jogging improves muscle endurance. The higher heart rate and sweating, along with other changes such as elevated blood pressure and higher level of some hormones, are responses to the exercise stress. These responses lead to adaptations over time.
In addition to improving your strength and endurance, these adaptations can also lower your blood pressure and blood glucose, help your muscles burn more fat and reduce your risk of heart attack and stroke. You can realize these benefits with as little as 30 minutes of moderate-intensity activity each day. But doing more, either longer duration or higher intensity, can promote greater adaptations and benefits. You can get the same benefits from doing a shorter but more intense workout as you can from a longer but less intense exercise session.
Many people look for a shortcut to getting these benefits by reducing the exercise time needed. As little as 10 minutes per day of high-intensity exercise can be enough to improve fitness, which is the basis for several popular “10-minute” exercise programs. In fact, short bouts of very intense exercise can improve strength and aerobic fitness better than lower intensity exercise done for a longer time, which is why these programs include a vigorous combination of aerobic and strength exercises.
Advertisements for some exercise equipment suggest that they offer a shortcut to building muscle or burning fat. Abdominal exercise devices claim to help you reduce belly fat without doing traditional whole-body exercise. This is called spot reduction, and there is no evidence that it actually works. Sure, those exercise devices will help you build stronger abdominal muscles, but reducing body fat in your midsection (or anyplace else) requires burning calories through traditional exercise like walking, jogging or aerobics. Incidentally, most of those abdominal exercise machines are about as effective as traditional sit-ups, so you can save some money by doing it yourself.
The ultimate shortcut to achieving the benefits of exercise is an “exercise pill.” While there is no such thing now, research continues into a drug that can mimic or promote the exercise adaptations in the muscle. Even if this drug is discovered, there is no guarantee that it will be as effective as exercise. In the meantime, the only sure way to improve your health and fitness is to actually exercise. You can chose how long and how intense you want that to be, but there are no shortcuts, so you do need to get moving!
Brian Parr, Ph.D., is an associate professor in the Department of Exercise and Sports Science at USC Aiken where he teaches courses in exercise physiology, nutrition and health behavior.