Influence of physical activity on change in weight status as children become adolescents
ABSTRACT Physical activity (PA) has been shown to have a positive effect on weight status, but habitual physical activity declines as youth age, yet some adolescents do not gain weight.
To determine if changes in weight status over 5 years during adolescence are associated with changes in PA levels.
A longitudinal study of 377 girls and 388 boys tested initially at ages 9-11 years old and 5 years later (age 14-16 years old). The sample was grouped by initial and final weight status: N-N = youth with BMIs < 85(th) percentile at both points (n = 456; 60%); O-O = overweight youth with BMIs > or = 85(th) percentile at both time points (n = 186; 24%); O-N = overweight youth whose BMI declined to < 85(th) percentile (n = 66; 9%); N-O = normal weight youth who became overweight (n = 57; 7%). Stature and body mass were measured and habitual PA levels were obtained during the survey.
Total PA scores, moderate (MPA) and vigorous activity (VPA) declined by 65-70% for all groups (p = 0.002). Girls in the O-N groups had less of a decline in PA than the girls in the N-O group (p < 0.05). No differences were evident for the boys. These results were consistent even when adjusted for developmental stage or race/ethnicity.
Overweight children as young as 9 years old are already participating in less PA than normal weight youth. Although PA declined from childhood to adolescence, overweight girls with normalized weight status, had less of a decline in MPA or VPA than normal weight girls who became overweight. The data highlight the complexity of the interrelationship between physical activity and weight gain or loss. These data suggest that habitual physical activity levels, especially in girls, may have a role in adolescents attaining a healthy weight status.
- SourceAvailable from: Mathieu Bélanger
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- "In the present study, we examine the association between individual trajectories of physical activity across secondary school, with change in adiposity in boys and girls separately, using growth curve modeling. Sex-specific analyses were used because of previously demonstrated sex differences in the association between physical activity and body fat changes during adolescence  . "
ABSTRACT: Findings from prospective studies on associations between physical activity and adiposity among youth are inconsistent. Our aim was to describe physical activity trajectories during secondary school and examine the association with change in adiposity in youth. Physical activity was measured in 20 survey cycles from 1999 to 2005; anthropometrics were measured in survey cycles 1, 12, and 19. Individual growth curves modeling moderate-to-vigorous physical activity (MVPA) and vigorous physical activity (VPA) were estimated. Estimates of initial level and rate of decline in MVPA and VPA bouts per week were included as potential predictors of body fat% and body mass index using age- and sex-specific linear regression. Complete data were available for 840 and 760 adolescents aged 12-13 years at baseline, followed from survey cycles 1-12 and 12-19, respectively. Among girls, yearly declines of one MVPA and one VPA bout per week during earlier adolescence were associated with increases of 0.19 (95% confidence interval [CI], 0.02-0.36) and 0.47 (95% CI, 0.015-0.92) units of body fat%, respectively. In boys, a yearly decline of one MVPA bout per week was associated with an increase of 0.38 (95% CI, 0.05-0.70) units of body fat% during later adolescence. Obesity prevention programs should include strategies to prevent declines in physical activity.Annals of epidemiology 09/2013; 23(9):529-33. DOI:10.1016/j.annepidem.2013.07.004 · 2.15 Impact Factor
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- "Dishman, Sirard, & Pate, 2007; Sirard, Pfeiffer, Dowda, & Pate, 2008), females who mature early (Baker, Birch, Trost, & Davison, 2007; Davidson, Werder, Trost, Baker, & Birch, 2007) and youth who are overweight (McMurray et al., 2008; Trueth et al., 2007). Males have higher levels of typical physical activity than females; for both, activity tends to decline over the progression from elementary and middle school through grade 12 (Eaton et al., 2008). "
ABSTRACT: This article provides an introduction to the October 2011 special issue of the Journal of School Health on "Healthier Students Are Better Learners." Literature was reviewed and synthesized to identify health problems affecting school-aged youth that are highly prevalent, disproportionately affect urban minority youth, directly and indirectly causally affect academic achievement, and can be feasibly and effectively addressed through school health programs and services. Based on these criteria, 7 educationally relevant health disparities were selected as strategic priorities to help close the achievement gap: (1) vision, (2) asthma, (3) teen pregnancy, (4) aggression and violence, (5) physical activity, (6) breakfast, and (7) inattention and hyperactivity. Research clearly shows that these health problems influence students' motivation and ability to learn. Disparities among urban minority youth are outlined, along with the causal pathways through which each adversely affects academic achievement, including sensory perceptions, cognition, school connectedness, absenteeism, and dropping out. Evidence-based approaches that schools can implement to address these problems are presented. These health problems and the causal pathways they influence have interactive and a synergistic effect, which is why they must be addressed collectively using a coordinated approach. No matter how well teachers are prepared to teach, no matter what accountability measures are put in place, no matter what governing structures are established for schools, educational progress will be profoundly limited if students are not motivated and able to learn. Particular health problems play a major role in limiting the motivation and ability to learn of urban minority youth. This is why reducing these disparities through a coordinated approach warrants validation as a cohesive school improvement initiative to close the achievement gap. Local, state, and national policies for implementing this recommendation are suggested.Journal of School Health 10/2011; 81(10):593-8. DOI:10.1111/j.1746-1561.2011.00632.x · 1.66 Impact Factor
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