Correlates of leisure-time physical activity differ by body-mass-index status in Brazilian adults

The objective of this study was to evaluate physical activity (PA) levels in adults and their association with sex, age, and education level across categories of body mass index (BMI).

We conducted a population-based, cross-sectional study including 3100 individuals age >20 years living in Pelotas, Brazil. PA was assessed using the leisure-time section of the long International Physical Activity Questionnaire. "No PA" was defined as zero minutes of activity/ week; "insufficient PA" was defined as <150 minutes of activity/week; "high PA" was defined as > or =500 minutes of activity/week. BMI was categorized into normal (<25 kg/m2), overweight (25-29.9 kg/m2), and obesity (>or =30 kg/m2).

The prevalence of insufficient PA was 71.6% among normal BMI subjects, 71.3% among overweight individuals, and 73.7% among obese ones (P = .67). No PA and high PA were also not associated with BMI. The associations between sex, age, and education level and PA levels tended to be stronger among normal-weight individuals compared with overweight and obese individuals. Among the obese, most associations were not significant. Among normal-weight individuals, higher PA levels were observed in men, young adults, and those with higher education.

Variables associated with leisure-time PA differed between normalweight, overweight, and obese individuals. Studies on PA correlates might benefit from stratifying by BMI.