This groundbreaking new medical work demonstrates how modern sedentary lifestyles contribute to poor health, obesity, and diabetes, and how health can be dramatically improved by continuous, low-intensity, movement that challenges the force of gravity. Citing her original NASA research on how weightlessness weakens astronauts' muscles, bones, and overall health, the author presents a simple and effective plan for maintaining good health throughout life by developing new lifestyle habits of frequent gravity-challenging movement. Written for everyone who spends most of their lives sitting in chairs, at desks, and in cars, this practical, easy-to-follow action plan outlines simple gravity-challenging activities such as standing up frequently, stretching, walking, and dancing that are more healthful and effective than conventional diet and exercise regimens.