Effects of extra school-based physical education on overall physical fitness development--the CHAMPS study DK.

First, this study aimed to investigate if four extra physical education (PE) lessons per week improved children's development in physical fitness. Second, to investigate if the extra PE lessons improved development in physical fitness for children with lower levels of fitness at baseline. This study was a longitudinal controlled school-based study. The study population consisted of 10 Danish public schools with children in preschool to fourth grade (cohorts 0-4) with 2.5-year follow-up. Six schools had extra PE and four schools had normal PE. In total 1247 children were included (normal PE = 536, extra PE = 711). Development in fitness was analyzed using a composite z-score from six fitness tests. Multilevel mixed-effects linear regression was used to examine the association between school type and development in fitness. Extra PE increased the total development of composite z-score units among children enrolled in cohort 4 and borderline in cohort 3 with 1.06 (95% confidence interval 0.48-1.65) and 0.52 z-score units (-0.06 to 1.09), respectively. Children in the lower 50 percentiles increased their development with 0.47 (0.08-0.85) z-score units. Extra PE in schools improved development in fitness for cohort 4 and borderline for cohort 3 among all children. Extra PE improved fitness development across all cohorts among children with low fitness levels.

Prospective association of adiposity and cardiorespiratory fitness with cardiovascular risk factors in healthy children.

This study aimed to examine the prospective association of three different measures of adiposity and cardiorespiratory fitness (CRF) with 2-year change in cardiovascular disease (CVD) risk factors in children. Two-year longitudinal data in schoolchildren aged 7-11 years (n = 365-729) was used. Total body fat (TBF) from dual-energy x-ray absorptiometry, body mass index (BMI), waist circumference (WC), CRF, blood samples, and blood pressure were obtained in 2008 and 2010 in the Childhood Health, Activity, and Motor Performance School Study in Denmark (CHAMPS study-DK). Greater adiposity at baseline was associated with increased CVD risk factor levels at follow-up. The magnitudes of associations were similar regardless of adiposity measure [TBF%: ß 0.30, 95% confidence interval (CI): 0.21-0.39; BMI: ß 0.24, 95% CI: 0.14-0.33; WC: ß 0.20, 95% CI: 0.10-0.31], and no evidence of nonlinear relationships was observed. We found less strong associations of CRF with increase in CVD risk factor levels after adjusting for adiposity; however, increasing CRF was still favorably associated with decrease in CVD risk factor levels among boys. Results suggest that any effort to shift the population distribution of adiposity downward would be valuable for early CVD prevention. The association of CRF with CVD risk factors was largely explained by adiposity, particularly among girls.

Overuse and traumatic extremity injuries in schoolchildren surveyed with weekly text messages over 2.5 years.

The objectives of this prospective cohort study were to report the incidence, prevalence, and duration of traumatic and overuse injuries during a period of 2.5 years and to estimate the odds of injury types. In all, 1259 schoolchildren, aged 6-12, were surveyed each week with an automated mobile phone text message asking questions on the presence of any musculo-skeletal problems and participation in leisure-time sport. Children were examined and injuries classified as overuse or traumatic. The overall injury incidence and prevalence were 1.2% and 4.6% per week, with 2.5 times more overuse than traumatic injuries in lower extremities, and mean injury duration of 5.3 and 4.8 weeks, respectively. A reverse pattern was found for upper extremities, with 3.1 times more traumatic than overuse injuries and mean durations of 3.3 and 5.2 weeks, respectively. Grade level, school type, leisure-time sport, and seasonal variation were associated with the risk of sustaining lower extremity injuries. Only grade level was associated with upper extremity injuries. The magnitude of overuse and traumatic limb injuries emphasizes the need for health professionals, coaches, and parents to pay special attention in relation to the growing and physically active child.