Anyone who watches cable TV is subjected to numerous ads for exercise equipment; these infomercials offer a vast array of devices that promise a lean, muscular physique, often with little effort on the part of those who use them. In fact, the human body is already equipped with the features needed to produce and maintain physical fitness.
Our musculoskeletal system, under the control of our nervous system, allows us to walk, run, swim, jump, climb and engage in a wide range of physical activities, all of which combat obesity, tone muscles and improve aerobic conditioning. Stair climbing is an excellent example of efficient, no-cost exercise that burns calories, strengthens muscles and benefits the cardiovascular system. For most adults, walking and swimming are the best forms of exercise, offering many benefits with little risk of injury; younger or more fit individuals might add jogging, situps, pushups and a variety of aerobic exercises but, in the end, no external equipment is necessary.
Of course, humans purchase and use a wide variety of things that are not required for their personal welfare and many succumb to the promise of six-pack abs and tight, muscular butts. It is, after all, better to exercise with that magical equipment than to spend the day on the couch.
