Abstract
The aim of this study was to analyze longitudinal associations between cardiorespiratory
fitness, physical activity and body mass index in a 4-year longitudinal study. 170
students (97 girls and 73 boys) aged at baseline from 11 to 17 years were followed.
Students performed 20-m-SR; physical activity patterns and parents’ education were
evaluated using a standard questionnaire. Body mass index was categorized according
to established cut points. In a multilevel analysis using MLwIN, 2 level structures
were defined: first for individuals and second for time observations. In a longitudinal
2 level analysis, cardiorespiratory fitness was negatively associated with body mass
index for girls and boys, respectively (p<0.05; R2=0.63; 0.62), especially with obesity category (p<0.01; R2=0.58; 0.60). In girls, independent associations were observed between CRF and PA
categories regarding participation “almost every day” in organized (p<0.05; R2=0.50) and non-organized sports outside school (p<0.05; R2=0.52) and participation in sports competitions (p<0.05; R2=0.51). In boys, associations were found only with participation in sports competitions
(p<0.05; R2=0.50). The results highlight the importance of youth participation in organized activities
and competitive sports over time to achieve health-related fitness benefits.
Key words
longitudinal study - physical activity - cardiorespiratory fitness - body mass index
- adolescence
