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Updated: Jun 20, 2026

Visualization of Intensity Levels to Reduce the Gap Between Self-Reported and Directly Measured Physical Activity
Published on: March 7, 2019
Changes in physical activity among Brazilian adults over a 5-year period
Alan Goularte Knuth1, Giancarlo Bacchieri, Cesar Gomes Victora
1Post-graduate Program in Epidemiology, Federal University of Pelotas, Pelotas, Brazil. alan_knuth@yahoo.com.br
Background:
The aim of this study was to document changes in physical activity of Brazilian adults by comparing two surveys carried out 5 years apart.
Methods:
Two population-based cross-sectional surveys were carried out in the city of Pelotas, Brazil, in 2002 and 2007. Their multistage sampling strategies were virtually identical. The first study included 3182 and the second 2986 adults aged 20 years or older. The short version of the International Physical Activity Questionnaire (IPAQ) was used in both surveys, and individuals were classified as insufficiently active if reporting less than 150 min per week, according to a score combining moderate-intensity and vigorous-intensity physical activity.
Results:
Prevalence of insufficient physical activity increased from 41.1% (95% CI 37.4 to 44.9) in 2002 to 52.0% (95% CI 49.1 to 53.8) in 2007. A 70% increase in prevalence of insufficient physical activity (p=0.008) was observed among poor individuals, whereas there was no significant change in the better-off. In contrast to the direct association between insufficient physical activity and socioeconomic level found in 2002, the 2007 survey showed no association. In the 2007 multivariable analysis, insufficient physical activity was directly associated with age and inversely with schooling.
Conclusion:
Effective interventions for the promotion of physical activity are urgently required in order to overcome the decline in physical activity levels in this population, particularly among the poor.
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