Are You Really Getting Enough Exercise?
According to the experts at Harvard Medical School, to get the full benefit of your workout, you need to know how hard you’re exercising, and that can be different for everyone. The national exercise guidelines are pretty general. They recommend 30 minutes of moderate aerobic exercise on most days and strength training on two to three days each week. But what does this mean to you as an individual? As it turns out, fulfilling the exercise requirements may depend on several things, including your age, resting heart rate, muscle strength, and present level of conditioning.
What is exercise?
Dr. Howard Knuttgen, research associate in physical medicine and rehabilitation at Harvard-affiliated Spaulding Rehabilitation Hospital, says that having a full understanding of what you’re doing when you exercise is important. He defines exercise as any activity requiring you to generate force by using your muscles. The more force you exert, the more exercise you get. In general, aerobic, or cardiovascular, workouts call for moving your body (for instance, by walking, running, cycling, rowing, or swimming), and strength-building workouts involve moving an object (for instance, by lifting weights or using resistance machines).
Getting enough aerobic exercise
Two keys to cardiovascular conditioning are intensity and amount. Exercise shouldn’t be effortless, but it shouldn’t bring you to the brink of collapse.
Intensity. The guidelines suggest brisk exercise, but what does that mean? A brisk clip for some people can be a snail’s pace for others. Fortunately, your body offers some clues. The most commonly suggested measure is whether or not you can carry on a conversation while you are walking or running. If you can’t, you’re probably exercising too strenuously to keep going for 30 minutes and should slow down. But if you can sing, you probably need to step up your pace.
Duration. Recently, high-intensity workouts as brief as four to seven minutes have been promoted as a way to keep fit. Dr. Knuttgen is very skeptical. He has a file of articles and ads promoting exercise regimens that offer to keep you fit with little investment of either time or effort. “This is exercise quackery. If a program sounds too good to be true, it probably is,” he says. The same goes for skimping on the number of weekly sessions. “Exercising once a week won’t contribute much to your fitness; two weekly sessions should have considerable value; but three are desirable,” he advises. “A greater number of exercise sessions per week should provide even greater benefit.”
Making strength training count