Prevalência e fatores associados a níveis insuficientes de atividade física em jovens estudantes de duas cidades Brasileiras: últimos sete dias e semana típica ou normal

this study compared the prevalence rates of insufficient physical activity levels and of certain related factors determined for using physical activity measure during in the past seven days, and in a typical week. this is a cross-sectional analysis (baseline data) of a school-based randomized trial (the saude na boa project), including 2,096 students (15-24 years of age; 55.6% females) from 10 schools in florianopolis and 10 schools in recife, pair-matched by size and location. data were collected by a previously validated questionnaire. individuals who reported performing moderate to vigorous intensity physical activities lasting > 60 minutes, > 5 days per week were classified as "active" and the remainders of the sample were classified as "insufficiently active". this classification was performed on the basis of the activity performed during two reference periods: last seven days and typical week. the measure of the physical activities considering the period reference of last the seven days resulted in higher prevalence of insufficient levels of physical activity in comparison to the measure considering the reference of typical week (60.8% vs. 54.6%; p < 0.001). the factors associated with and insufficient level of physical activity, and the magnitudes of the measures of association were similar for two reference periods. independent of the reference period adopted for recall the physical activities, the insufficient levels of physical activity had been identified to the same associated factors, with a little variation in the magnitude of the measures of association. to use past seven days or typical week as reference period to measure the levels of physical activity seems to generate different prevalence of insufficient levels of physical activity, but same associated factors.