Associations of cardiorespiratory fitness, adiposity, and arterial stiffness with cognition in youth.

PURPOSE: To investigate the associations of cardiorespiratory fitness, adiposity, and arterial stiffness with cognition in 16- to 19-year-old adolescents. METHODS: Fifty four adolescents (35 girls; 19 boys) participated in the study. Peak oxygen uptake (V̇O2peak ) and peak power output (Wmax ) were measured by the maximal ramp test on a cycle ergometer and ventilatory threshold (VT) was determined with ventilation equivalents. Lean mass (LM) and body fat percentage (BF%) were measured using a bioelectrical impedance analysis. Aortic pulse wave velocity (PWVao) and augmentation index (AIx%) were measured by a non-invasive oscillometric device. Working memory, short term memory, visual learning and memory, paired-associate learning, attention, reaction time, and executive function were assessed by CogState tests. RESULTS: V̇O2peak /LM (ß = 0.36 p = .011) and Wmax /LM (ß = 0.30 p = .020) were positively associated with working memory. Wmax /LM was also positively associated with visual learning (ß = 0.37, p = .009). V̇O2 at VT/LM was positively associated with working memory (ß = 0.30 p = .016), visual learning (ß = 0.31 p = .026), and associated learning (ß = -0.27 p = .040). V̇O2 at VT as % of V̇O2peak , BF%, PWVao, and AIx% were not associated with cognition. CONCLUSION: Cardiorespiratory fitness was related to better cognitive function, while BF% and arterial stiffness were not associated with cognition in adolescents.

Longitudinal associations of physical activity and pubertal development with academic achievement in adolescents.

OBJECTIVE: We sought to investigate the longitudinal associations of moderate-to-vigorous physical activity (MVPA) and pubertal development with academic achievement in adolescents. METHODS: A total of 635 adolescents (283 boys, 352 girls) aged 11-13 years participated in the study. MVPA was assessed by the Health Behaviour in School-aged Children study questionnaire, and pubertal development was assessed by the Pubertal Development Scale at beginning of the 6th grade (baseline) and end of the 7th grade (follow-up). Grade point average (GPA) at the end of Grades 5 and 7 was computed from data acquired from the school registers. The data were analyzed using linear regression and analyses of covariance. RESULTS: In boys, MVPA was positively associated with GPA at baseline after adjustment for age (ß = 0.144, 95% confidence interval (CI): 0.028-0.260, p = 0.028). In girls, the Pubertal Development Scale was positively associated with GPA at baseline (ß = 0.104, 95%CI: -0.004 to 0.211, p = 0.058) and follow-up (ß = 0.104, 95%CI: -0.002 to 0.211, p = 0.055) after adjustment for age, and these associations strengthened after further adjustment for MVPA (p < 0.05). Adolescents who were inactive at baseline or at baseline and follow-up had lower GPA during follow-up than their continuously highly active peers (mean difference = -0.301, 95%CI: -0.543 to -0.058, p = 0.009) and all other adolescents (mean difference = -0.247, 95%CI: -0.475 to -0.019, p = 0.029). These differences were greater in girls than in boys. CONCLUSION: Lower levels of MVPA were associated with lower GPA in boys at baseline. Girls who were continuously inactive had lower GPA over the follow-up period than those who were continuously active. Finally, earlier pubertal development was associated with better academic achievement in girls.

Changes in physical activity and sedentary time in the Finnish Schools on the Move program: a quasi-experimental study.

The aim of the Finnish Schools on the Move program is to create a more active and pleasant school day through physical activity (PA). In this quasi-experimental design, we compared changes in moderate-to-vigorous-intensity physical activity (MVPA) and sedentary time (ST) during the school day and outside school hours for Grades 1-9 over two academic years in four program schools and two reference schools. Altogether 319 girls and boys aged 7-15 participated in the study between 2010 and 2012. MVPA and ST were measured four times over the 1.5-year follow-up period for seven consecutive days, using a hip-worn ActiGraph accelerometer. Linear growth curve modeling was used to examine the effect of the program on MVPA and ST during follow-up. School day MVPA increased (P = 0.010) and school day ST decreased (P = 0.008) in program primary schools (Grades 1-6) more compared with the reference schools. The effect sizes (Cohen's d) for the difference in change (from the first to the last measurement) were small (d = 0.18 and d = -0.27, respectively). No differences in the changes of leisure-time or whole-day MVPA and ST between the program and reference schools were observed during follow-up. In conclusion, the changes in school day MVPA and ST did not translate into positive effects across the whole day. More effective and longer promotion actions are needed for positive changes in PA and ST, especially in lower secondary schools and for all daily segments.

Recess physical activity and school-related social factors in Finnish primary and lower secondary schools: cross-sectional associations.

BACKGROUND: Participation in physical activities provides students with opportunities for social interaction and social skills development. The purpose of this study was to investigate the associations of students' recess physical activity with school-related social factors. METHODS: Data were collected in 19 schools countrywide in autumn 2010, and 1463 students from grades 4 and 5 (primary school) and from grades 7 and 8 (lower secondary school) completed an anonymous questionnaire. Multiple linear regression analysis was used to investigate whether self-reported physical activity at recess was associated with peer relationships at school, relatedness to school and school climate. Analyses were adjusted for self-reported overall physical activity and conducted for primary and lower secondary schools. Multi-group analysis was used to test sex differences among the associations. RESULTS: In primary school, physical activity at recess was positively associated with peer relationships at school (boys: b = 0.17, p = 0.007 and girls: b = 0.21, p <0.001), relatedness to school (boys: b = 0.18, p = 0.002 and girls: b = 0.24, p <0.001) and school climate (girls: b = 0.17, p = 0.001), after adjusting for overall physical activity. In lower secondary school, physical activity at recess was positively associated with peer relationships at school (boys: b = 0.09, p = 0.006 and girls: b = 0.12, p = 0.010) but not with other school-related social factors. No sex differences were observed in these associations. CONCLUSIONS: Our results suggest that students' participation in physical activities during school recess is positively associated with students' school-related social factors. In the future, it would be worthwhile to study how physical activity at recess should be organised in order to support the development of school-related social factors.