BERNSTEIN MS, COSTANZA MC, MORABIA A.
Association
of Physical Activity Intensity Levels with Overweight and Obesity
in a Population-Based Sample of Adults.
Prev Med
2003 (in press).
Abstract
Background. Clarify the association between physical activity
intensity and overweight/obesity.
Methods. Population-based 1997–2001 survey in Geneva,
Switzerland (n = 5,757, ages 35 to 74). Intensity of physical
activity energy
expenditure (EE) defined as percentage of total EE in moderate
activities [3–3.9 basal metabolism rate (BMR), e.g., normal
walking,
household chores] and high-intensity activities (z4 BMR, e.g.,
brisk walking, sports). Overweight or obesity based on measured
body
mass index (BMI).
Results. Comparing participants in the lowest vs. the highest
tertile of the percentage of high-intensity EE, the odds ratios
(ORs) were, for
obesity vs. normal weight, 2.8 (95% confidence interval: 2.0–3.8,
P < 0.0001) in men and 2.4 (1.7–3.4, P < 0.0001) in
women. For obese vs.
overweight, the men/women ORs were 1.9 (1.4–2.6, P <
0.0001)/1.5 (1.0–2.2, P < 0.05). For overweight vs. normal
weight, the men/women
ORs were 1.4 (1.1–1.7, P < 0.002)/1.7 (1.3–2.1,
P < 0.0001). Less or no relationship was found for the percentage
of moderate-intensity EE.
Conclusions. This cross-sectional study cannot determine whether
exercise is an effective strategy for weight control or whether
overweight
or obese people exercise less. However, clear dose–response
associations in both genders between obesity or overweight and
energy
expenditure in high (but not in moderate)-intensity activities
are findings with potentially major public health implications
meriting validation in
an experimental intervention study.
Keywords: Body mass index; Body weight; Energy metabolism;
Exercise; Obesity; Overweight
This study was partly supported by the Swiss
National Fund for Scientific Research Grant no.32-37986.93.
