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Activity and Fitness Health Benefits

 Fitness & Health

Physical Activity, Fitness, and Health

Would you be upset to learn that according to the U.S. Department of Health and Human Services, unhealthy eating and physical inactivity causes 310,000 to 580,000 deaths every year in the United States? That these lives are lost by simply failing to apply a medically proven therapy? It’s true. Our high-cost health care system has ignored a simple, low-cost health treatment with the capacity to save hundreds of thousands of lives and billions of dollars. This miracle treatment goes unused in favor of expensive drugs, costly operations, and even organ transplants. How could this happen? One contributing factor is that physicians are compensated for performing procedures rather than providing the counseling that leads to improved health habits. Additionally, with the development of penicillin and other wonder drugs, we patients have sought a quick fix for problems and have relinquished personal responsibility for our health. Hospitals, drug and insurance companies, and yes, even lawyers, have reaped enormous profits in this so-called health care system while simple, inexpensive health habits have gone unused.

Fortunately, the times are changing. As we work to rebuild our ailing health care system, we are searching for ways to reduce costs and the reliance on drugs and medical procedures. At the same time, researchers are questioning the value of certain operations and drugs, and confirming the contributions of physical activity and related habits to health, longevity, and the quality of life. Finally, local, state, and federal organizations are moving to increase physical activity and curb the rise in sickness and death associated with inactivity. This section reviews studies that provide the modern foundation for the relationship of physical activity and fitness to physical and psychological health. It discusses the benefits and risks of activity, catalogs the extra benefits of fitness, and provides advice to help you begin your transformation to health, vitality, and the active life.

Activity and Fitness Health Benefits

 Exercise is medicine.

American College of Sports Medicine (ACSM) and the American Medical Association (AMA)

The idea that physical activity is associated with good health is not new. The Chinese have long practiced tai chi and other forms of activity to prevent diseases associated with sedentary living. In Rome more than 1,500 years ago, the physician Galen prescribed exercise for health maintenance. References to the health values of exercise appear throughout recorded history, usually with little measurable effect on the populace. Why, then, do we invest time and energy to provide the latest evidence on the relationships among physical activity, physical fitness, and health? One reason is that we are devout optimists, the product of many years of professional experience and numerous success stories. Another reason is that never before have so many studies demonstrated so much about the health benefits of activity and fitness.

The Exercise is Medicine initiative was launched by the American College of Sports Medicine (ACSM) and the American Medical Association (AMA) in 2007. It calls for physical activity to become a standard component of disease prevention and medical treatment. The initiative urges health care providers to assess and review patient’s physical activity programs, and include exercise clearance, exercise prescription, and referrals to qualified health and fitness professionals in standard office visits. Patients are encouraged to discuss physical activity with their doctors and to learn how to continue or improve their physical activity programs. The initiative acknowledges that physical activity is crucial to the prevention, management, and treatment of numerous chronic conditions, including heart disease, type 2 diabetes, obesity, high blood pressure, and some cancers. While exercise clearly benefits the function and appearance of the body, the Exercise is Medicine campaign focuses on the internal benefits and how these benefits contribute to longevity and the quality of life  .

We concur that exercise is powerful medicine, but you don’t need to visit your doctor in order to get started on a program of regular, moderate physical activity. The goal of this book is to encourage a lifetime commitment to activity, fitness, and the active life.

Epidemiology, the study of epidemics, is a fitting way to study the modern epidemic—diseases of lifestyle—that is responsible for more than half of all deaths in the United States. The epidemiologist studies populations to determine relationships between behaviors, such as physical activity, and the incidence of certain diseases. Researchers look at morbidity (sickness) and mortality (death). Studies can be retrospective, looking back at past behaviors, or prospective, following a group into the future. Cross-sectional research looks at chronological slices of the population. Lack of solid information on activity, fitness, and other health habits often confound retrospective studies, whereas prospective studies face problems such as changing habits and dropout among participants. Issues of access to medical records (confidentiality) plague many studies, but the major problem is that of self-selection. Critics argue that subjects are physically active because they are well, not necessarily well because they are active.

Because self-selection confounds the results of retrospective and cross-sectional studies, only carefully controlled prospective studies, involving random assignment of participants to levels of activity (or inactivity), allow cause-and-effect conclusions. Because these studies are difficult to conduct and are most likely unethical because inactivity is dangerous to health, we may never have absolute proof of the value of activity and fitness. But when the preponderance of studies confirm the health benefits of activity and when the risks and costs of being active are minimal, recommending a prudent, if not totally proven, course of action seems reasonable.

Space does not permit a comprehensive review of the role of activity and fitness in health and disease, so this chapter reviews several classic studies and provides a summary of epidemiological research. To avoid endless 
details, it summarizes the effects of activity and fitness with reference to the risk ratio (RR), the ratio of morbidity or mortality for the active members of the population to that for the inactive members. Then, it discusses plausible mechanisms or reasons that activity may have beneficial effects and provides guidelines for recommended activity.

This chapter will help you do the following:

  • Determine the health benefits of physical activity and fitness
  • Understand the relationships among physical activity, fitness,and health
  • Appreciate how activity reduces the risk and severity of chronic diseases such as heart disease, diabetes, and some cancers
  • Assess the role of activity in arthritis, osteoporosis, and lower back problems
  • Compare your current level of activity with recommended values
  • Define the amount of activity needed for health

 Risk Ratio

In a study of Harvard alumni, those with the least activity had 78.8 cardiovascular deaths per year per 10,000 study participants versus 43.0 for the most active, yielding a risk ratio of 54 percent (43.0 ÷ 78.8 = .54). Stated another way, the risk was 46 percent lower (100 − 54 = 46%) for the active alumni (Paffenbarger, Hyde, and Wing 1986).