ABSTRACT
As the science of exercise physiology developed over the last century, it became obvious that exercise, or planned physical activity, could have a host of therapeutic, health, and performance benets. While exercise has become a topic of scientic inquiry, the commercial value of weight loss has popularized packaged programs in the viewing public via infomercials, health clubs, and personal trainers. These exercise programs range from those too light for meaningful benets to extreme weight-loss programs. They are targeted indiscriminately at populations ranging from sedentary to highly motivated individuals wanting to make dramatic physical changes. What qualies as knowledge of exercise today-even among those who instruct others on tness-is unfortunately inˆuenced more strongly by commercial forces than by science.