Immediately switch to the next exercise for the next target muscle group, and repeat the first three steps. When done in this fashion, your workout will take no more than 12 or 15 minutes. For more information about Super-Slow resistance training, please see my interview with Dr. McGuff.
The take-home message here is that one of the best forms of exercise to protect your heart is short bursts of exertion, followed by periods of rest. You can do this Sprint 8-style using an elliptical machine or recumbent bike, or you can do it using McGuff’s Super-Slow resistance training strategy. Ideally, you’ll want to do a little bit of both.
By exercising in short bursts, followed by periods of recovery, you recreate exactly what your body needs for optimum health. Heart attacks don’t happen because your heart lacks endurance. They happen during times of stress, when your heart needs more energy and pumping capacity, but doesn’t have it. So rather than stressing your heart with excessively long periods of cardio, give interval training a try.
Most importantly, during any type of exercise as long as you listen to your body you shouldn’t run into the problem of exerting yourself excessively. And, with interval training, even if you are out of shape you simply will be unable to train very hard, as lactic acid will quickly build up in your muscles and prevent you from stressing your heart too much.