Commentaries on Physical Activity and Health
Physical activity is the “best buy” for Americans
by Kenneth Powell, MD, MPH
In 1994, Professor Jeremy Morris, speaking at a symposium honoring Dr. Ralph Paffenbarger’s 70th birthday, proclaimed physical activity as the “Best Buy in Public Health.”1 Morris and Paffenbarger are the founding fathers of physical activity as a public health issue because of their seminal epidemiologic research in the 20th century. Today, more than 20 years later, bargain-hunting American consumers who usually buy anything “on sale,” aren’t buying. For more than 20 years, the estimated proportion of Americans meeting the recommended volume for weekly physical activity has been stable. Little or no change has occurred except when the measurement device or the definition of recommended activity has changed. Americans today are less active than Americans 50 years ago because the volume of “baseline physical activity” – the physical activity of everyday activities – has declined. Most Americans who meet current guidelines are no more and probably less active than the less active comparison groups in the research studies of Professors Morris and Paffenbarger. Was Dr. Morris wrong? Is physical activity not the “best buy” we thought it was? And if it is, why aren’t we buying?
Professor Morris was not wrong. Physical activity was and remains a best buy. In fact, subsequent scientific research has shown physical activity to be an even better buy than we thought. If physical activity were a pill every doctor would be prescribing it, every insurance company would be happy to pay for it, and every American would be taking it on a daily basis. The breadth of physical and mental health benefits is breathtaking. Regular physical activity significantly reduces the risk of premature death, coronary heart disease, stroke, high blood pressure, type 2 diabetes, breast and colon cancer, excessive weight gain, and injurious falls; it maintains functional ability in older adults, helps maintain weight loss, and reduces the risk of hip fracture and osteoporosis. Regular physical activity not only prevents disease, it helps treat it. People with heart disease, chronic obstructive lung disease, diabetes, cancer, and others all benefit from regular physical activity.
Some of the most exciting news concerns the benefits of physical activity on brain health. We now know that regular physical activity influences the structure and function of the brain for people of all ages. Regular physical activity enhances the cognitive processes of executive control, such as working memory, ability to focus, and flexibility; it increases processing speed. As a result we learn better and perform better on cognitive tests and solving the problems of daily life. It reduces the symptoms of depression and reduces the risk dementia including Alzheimer disease. Perhaps most importantly, regular physical activity simply makes us feel better. We sleep better, have more energy, feel better about ourselves, and are less subject to anger and frustration. We are happier.
If physical activity is such a good buy, then why aren’t people buying? Of the many reasons, here are a few that I think most important.
American culture – our social environment and built environment – inhibits a physically active lifestyle. Our schools, worksites, transportation systems, and communities are designed to minimize physical activity and have been very successful in doing so. In addition, our culture as reflected by our governmental expenditures fails to prioritize prevention. Almost all of our health expenditures are spent on disease treatment. Government public health activities comprised only 2.6% of national health expenditures.2
In spite of impressive scientific and workforce gains within the field of physical activity itself, both the public health and clinical care communities consider physical activity to be merely a personal choice and relegate it to low priority status. Within public health, physical activity lacks the fear engendered by infectious diseases, the malevolence of the tobacco industry, the social stigma of obesity, and the immediate demands of symptomatic illness. In the scramble for scarce prevention-focused funds, regular physical activity is pushed to the side. Within clinical care services, physical activity is not a pill, an implantable device, or a surgical procedure. There is paltry remuneration for time spent counselling patients about physical activity and it disappears from the problem list.
Finally, we have made people think that the benefits of regular physical activity derive only from high intensity activity and only after a certain threshold has been exceeded. As a result, those who would benefit the most – the most inactive of our fellow citizens – are led to believe that they must achieve a higher rate of energy expenditure than they have achieved in many years and that they must do so for at least 150 minutes per week before they reap any benefits whatsoever. In addition, they must make this impossible effort to reduce the risk of a disease they might or might not get 20 or 30 years from now. Not only have we failed to explain that they only need to exceed their current level of activity to benefit and that even light intensity activity is beneficial, we have also failed to tell them that they will feel better, sleep better, and have more energy right away. No wonder they don’t give it a second thought.
All of these things – the structure of our communities, the obligatory sitting behavior at school and at work, the inadequate emphasis on prevention, lack of respect within public health and clinical care circles, and a faulty goal impossible to achieve and with no early payoff – can be changed. And I think we are ready to do so.
The work of Professors Morris and Paffenbarger and those who came after them have set the stage. Physical activity is a popular field of endeavour at most if not all schools of public health, creating a knowledgeable and energetic workforce. We have a scientific journal devoted to physical activity and public health. We have physical activity guidelines issued by the U.S. Department of Health and Human Services. We have a National Physical Activity Plan. There is an International Society for Physical Activity and a Physical Activity Observatory endorsed by the Lancet. These signs indicate that our field – physical activity and public health – has matured. We have never had the kind of support that a “best buy” deserves but we have made great strides. We have more to do but we should not forget how much we have accomplished.
What do we need to do to surpass the tipping point where the American public finally begins taking up this “best buy in public health”? There are multiple correct answers to this question. Here are a few ideas. The American public would be more active if: 1) Community, state, and federal decision makers exchanged their pallid endorsements for active engagement and greater resources. 2) Business leaders acted in their own best interests by promoting physical activity during the journey to work, at the work site, and after work. 3) Civic leaders and city planners required all new developments and all changes to existing developments to foster and facilitate physically active transportation and living. 4) Educators built new schools in residential neighbourhoods, and enabled and encouraged students to be more active during school, before and after school, and going to and from school. 5) Media messages and press interviews emphasized the immediate positive benefits of regular physical activity – more energy, better sleep, happiness, improved cognition. 6) Federal and state agencies augmented current surveillance systems to include environmental conditions, public and private policies, and a broader range of types and intensities of physical activity.
Our research would be more productive if : 1) Researchers stopped evaluating so many behavioural change interventions among volunteer populations and started evaluating the “natural experiments” – the spontaneous environmental and policy changes – that occur frequently in our society. 2) Researchers and Program implementers collaborated on multifaceted community-wide interventions instead of smaller more easily evaluated interventions.
Finally, there are things every one of us can and should do. I am sure that your physical activity-related professional projects are helping. But ask yourself how you could modify them to make them more helpful. Ask your colleagues how you could augment them, or merge them with your colleague’s project to make both better. In addition, ask someone from a pertinent but different field from yours how you could make your projects better. Organize discussions among colleagues and any interested parties about how you, as a group, could better advance the field of physical activity and public health.
You should also ask yourself how your personal behaviour could encourage a more physically active culture. Ask your mom or dad if they would go for a walk with you. Send your kids outdoors to play. Volunteer to be the physical activity representative on your child’s School Health Committee. Be a role model not of athleticism but of healthful physical activity behaviour.
There are many things you can do. They may seem small. But enough small pieces add up to something big. Big enough that Americans surely will buy into the “best buy in public health”.
Kenneth E. Powell, MD, MPH, is a public health consultant. He was an epidemiologist with the Centers for Disease Control and Prevention and worked with the Georgia Department of Human Resources. He also served on the Physical Activity Guidelines Advisory Committee for the U.S. Department of Health and Human Services and is a member of the Physical Activity Work Group for the Task Force for the Guide to Community Preventive Services. He is a Fellow of the American College of Physicians, American College of Epidemiology, and American College of Sports Medicine. He was the recipient of the 2015 National Physical Activity Plan Honor Award.
1 Morris JN. Exercise in the prevention of coronary heart disease: today’s best buy in public health. Med Sci Sports Exerc 1994;26:807-814.
2 CDC. Health United States, Table 103. National health expenditures, average annual percent change, and percent distribution, by type of expenditure: United States, selected years 1960–2013. http://www.cdc.gov/nchs/data/hus/hus14.pdf#103. Accessed June 2, 2015.
Suggested Commentary: Powell, K. (2015). Physical activity is the “best buy” for Americans. National Physical Activity Plan Alliance Commentaries on Physical Activity and Health, 1(1).