This investigation described the effects of exercise, walking, and cycling for transportation,
as well as the effect of overall nonexercise physical activity, on mortality in the
Shanghai Women's Health Study (1997-2004). Women without heart disease, stroke, or
cancer were followed for an average of 5.7 years (n = 67,143), and there were 1,091
deaths from all causes, 537 deaths from cancer, and 251 deaths from cardiovascular
diseases. Information about physical activity and relevant covariates was obtained
by interview. Proportional hazards models were used to estimate adjusted hazard ratios
and 95% confidence intervals. Exercise and cycling for transportation were both inversely
and independently associated with all-cause mortality (p(trend) < 0.05), but walking
for transportation was less strongly associated with reduced risk (p(trend) = 0.07).
Women reporting no regular exercise but who reported 10 or more metabolic equivalent
(MET)-hours/day of nonexercise activity were at 25-50% reduced risk (p(trend) < 0.01)
relative to less active women (0-9.9 MET-hours/day). Among women reporting the least
nonexercise activity (0-9.9 MET-hours/day) but reporting regular exercise participation,
exercise was associated with reduced mortality (hazard ratio = 0.78, 95% confidence
interval: 0.62, 0.99). These findings add new evidence that overall physical activity
levels are an important determinant of longevity, and that health benefit can be obtained
through an active lifestyle, exercise, or combinations of both.