PHYSICAL INACTIVITY: THE BIGGEST PUBLIC HEALTH PROBLEM OF THE 21ST CENTURY

PHYSICAL ACTIVITY: THE BIGGEST PUBLIC HEALTH PROBLEM OF THE 21ST CENTURY

Presenter: Blair SN

Arnold School of Public Health, University of South Carolina, USA

Sedentary habits are highly prevalent in most countries of the world.

In the u.s. approximately 25-35% of adults are inactive, meaning that

they have sedentary jobs, no regular physical activity program, and are

generally sedentary around the house and yard. Given that sedentary

and unfit individuals are at approximately two-fold higher risk for many

health conditions than those who are moderately active and fit, the

population attributable risk (par) of inactivity is high. In the aerobics

center longitudinal study (acls) the par for low fitness in more than 50,000

women and men followed for many years is 16-17% of deaths. This is far

higher than other putative risk factors for mortality. For example, obesity

accounts for 2-3% of deaths in this cohort. Another example from the

acls is that in 3,293 obese men (bmi ³30.0), 27% of the deaths might have

been avoided if none of the men had prevalent cardiovascular disease at

baseline whereas 44% of the deaths might have been avoided if none

of the men had been unfit. The independent relative risks for death are

comparable for prevalent cardiovascular disease (rr=2.4) and for low

fitness (rr=2.3). Over the past few decades we have largely engineered the

need for physical activity at home, on the job, and during leisure-time out

of the daily lives of most people in industrialized societies. To address the

major public health problem of physical inactivity we will need to consider

and evaluate societal, environmental, and individual approaches to making

physical activity more common for more people more of the time.