Although authorities advocate a ‘call to action’ to improve health and reduce illness and disability through increased physical activity, people are becoming less rather than more active. This trend is inversely related to economic development, thus, pervades middle- and low-income countries as well as high-income countries. Given that the health benefits of physical activity and the negative effects of inactivity are unequivocal, the translation of this well-established body of knowledge has lagged with respect to being implemented and reversing the high prevalence of lifestyle conditions. This article examines this 21st century phenomenon and identifies the simple evidence-based means of reversing this lethal trend through social and health policy and individual approaches. Through healthy and active living, the threshold for lifestyle conditions including ischemic heart disease, hypertension and stroke, cancer, diabetes, obesity, and osteoporosis could be increased, and their rate of progression and end-of-life morbidity decreased. Physical activity in conjunction with smoking abstinence and optimal nutrition has a primary role in the prevention of these deadly conditions and in some cases ‘cure’ as well as management. Further, the severity of the symptoms of other chronic conditions such as arthritis and depression may be decreased with active living resulting in superior health outcomes. In addition to managing the needs of people one-to-one, physical therapists (the fifth largest group of health care professionals and the only one committed to non invasive care) are uniquely positioned to serve as consultants in designing healthy communities, neighborhoods, schools, businesses, factories and health facilities. As exercise specialists in the 21st century, physical therapists can minimize the enormous social and economic burdens of lifestyle risk factors and conditions and enhance people's quality of life.