The numerous benefits of physical activity range from improvements in bone mineral density to ameliorating the effects of aging (Table 14.1). Not only are physically active individuals healthier, but they are also happier, live longer, sleep better, experience less pain, and have more energy and better day-to-day function. Many of these benefits can be attributed to simply increasing the amount of moderate physical activity in one's day and to increasing the amount of activity that works the heart, blood vessels, and lungs -- the cardiovascular and respiratory systems. This type of physical activity has many names that mean the same thing: cardiovascular, cardiorespiratory, aerobic, and endurance activity are all longer duration, rhythmic activities that use large muscle masses and require the utilization of oxygen to break down nutrients to produce energy.