Obesity and physical fitness of Latino children during the school academic year and the summer season: A longitudinal study. Rodriguez, Augusto X.University of Houston, ProQuest Dissertations Publishing, 2010. 3411293.

Childhood obesity in Latino children is a major health problem in the United States. A recent national estimate suggests that 36% of Latino children in the United States are overweight (Ogden, 2006). Poor aerobic fitness is considered a major factor associated with this obesity epidemic. The school environment is an optimal avenue for improving physical fitness through physical education, recess, and after school extracurricular activities. Research indicates that during the summer season, children may experience a decrease in physical fitness resulting in an increased risk for obesity (Christodoulos et al, 2007). Few studies have assessed longitudinally changes of body composition and aerobic capacity during the academic school year and summer season in children. Thus, the purpose of this study was to assess longitudinally changes over the academic school year (9.5 months) and summer season (2.5) on body mass index (BMI), percentage of body fat, and aerobic capacity in a sample of 119 Latino children (mean age = 9.2 ± 0.81). Archival data collected at three-time points (September 2004 (M1), May 2005 (M2), and September 2005 (M3)) were analyzed for this study. A general linear model repeated measures design was used to determine changes in selected variables. Findings revealed that 47% of the study children were overweight at a baseline. No statistically significant changes in BMI Z-scores over the academic year and summer season were observed. However, obesity status at baseline was a factor in influencing changes in BMI. Among overweight children, there was a significant decrease of BMI over the academic year compared to that of healthy weight children. Body fat percentage significantly increased over the academic year, and increased over the summer season. Aerobic capacity showed a significant increase over the academic school year, but did not change over the summer season, with boys exhibiting greater aerobic capacity scores than girls. In conclusion, results from this study demonstrate that the academic year has a positive impact on overweight children's BMI Z scores and aerobic fitness.