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The four components of fitness

This is an excerpt from Active Living Every Day-3rd Edition by Steven N. Blair,Andrea L. Dunn,Bess H. Marcus,Ruth Ann Carpenter & Peter E. Jaret.

So far in this book, we’ve focused on aerobic activities—such as walking, dancing, biking, swimming, and jogging—that burn calories and improve the health and fitness of your heart and lungs. But there are other aspects to fitness. Keeping your muscles healthy and strong is one. Muscle-strengthening activities are important because we often lose muscle strength when we don’t use our muscles and as a natural part of the aging process. The standard recommendation is to do a variety of 8 to 12 exercises that make the muscles in different parts of your body work harder than they are accustomed to working. Muscle-strengthening activities include push-ups and squats, using exercise machines or handheld weights, some yoga poses, and everyday activities such as carrying heavy loads or digging in the garden.

Two other aspects of fitness are balance and flexibility. They don’t burn a lot of calories, but they are important, especially as you age. Examples of activities that maintain or improve your balance include yoga, bicycling, and dance. They’re a key part of overall fitness because they can help you avoid falling—and falls are a major cause of injury in older adults. Maintaining flexibility is also important. Stretching exercises help to reduce the risk of injury as well by improving the ability of your limbs, muscles, and joints to move through their full range. Including flexibility exercises daily can help you do your aerobic, muscle-strengthening, and balance activities more effectively.

In this book, we focus on aerobic physical activities because they are usually an easy place for people to start moving more. What could be easier than getting up and taking a brief walk, right? But it’s important to remember that physical activities come in many forms and doing a mix of aerobic, muscle-strengthening, balance, and flexibility activities all contribute to good health and fitness.

How can you add these additional dimensions to your fitness routine? You’ll find some specific instructions for easy muscle-strengthening exercises and stretching exercises on ALED Online. Another good option is to check out stretching, yoga, or muscle-strengthening classes at local health and fitness centers. You can also find a variety of instructions for stretching and simple muscle-strengthening exercises online. The Move Your Way program offered by the Office of Disease Prevention and Health Promotion ( is a useful resource. But beware—not everything you find on the Internet is reliable. We recommend looking for resources that are associated with colleges, universities, and well-known medical institutions, such as Harvard Health or the Mayo Clinic.

As always, it’s a good idea to check with your doctor before making any dramatic change in your activities.

More Excerpts From Active Living Every Day 3rd Edition