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.