Highlights Moderate-to-vigorous and total physical activity are significantly positively associated with fundamental motor skills in the early years. Only 1 longitudinal study has explored mediation and found that perceived motor competence did not mediate the association between motor competence and total or moderate-to-vigorous physical activity. There is limited evidence from longitudinal studies to support or disprove the Stodden conceptual model that physical activity drives motor competence in early years and vice versa in later childhood.

Classroom-based physical activity (PA) interventions offer the opportunity to increase PA without disrupting the curriculum. We aimed to explore the feasibility and potential effectiveness of a classroom-based intervention on moderate to vigorous PA (MVPA) and total PA. The secondary aim was to assess the acceptability and sustainability of the intervention. In a mixed-methods, non-randomised, exploratory controlled before-and-after study, 152 children (10 ± 0.7 years) were recruited from five schools; two intervention (n = 72) and three control (n = 80) schools. School teachers delivered an 8-week classroom-based intervention, comprising of 10 minutes daily MVPA integrated into the curriculum. The control schools maintained their usual school routine. Mean daily MVPA (min), total PA (mean cpm), physical fitness, and health-related quality of life measurements were taken at baseline, end of intervention, and 4-weeks post-intervention (follow-up). Data were analysed using a constrained baseline longitudinal analysis model accounting for the hierarchical data structure. For the primary outcomes (MVPA and total PA) the posterior mean difference and 95% compatibility interval were derived using a semi-Bayesian approach with an explicit prior. The acceptability and sustainability of the intervention was explored via thematic content analysis of focus group discussions with teachers (n = 5) and children (n = 50). The difference in mean daily MVPA (intervention-control) was 2.8 (-12.5 to 18.0) min/day at 8 weeks and 7.0 (-8.8 to 22.8) min/day at follow-up. For total PA, the differences were -2 (-127 to 124) cpm at 8-weeks and 11 (-121 to 143) cpm at follow-up. The interval estimates indicate that meaningful mean effects (both positive and negative) as well as trivial effects are reasonably compatible with the data and design. The intervention was received positively with continuation reported by the teachers and children. Classroom-based PA could hold promise for increasing average daily MVPA, but a large cluster randomised controlled trial is required.

An understanding of all aspects of fluoride metabolism is critical to identify its biological effects and avoid fluoride toxicity in humans. Fluoride metabolism and subsequently its body retention may be affected by physiological responses to acute exercise. This pilot study investigated the effect of exercise on plasma fluoride concentration, urinary fluoride excretion and fluoride renal clearance following no exercise and three exercise intensity conditions in nine healthy adults after taking a 1-mg Fluoride tablet. After no, light, moderate and vigorous exercise, respectively, the mean (SD) baseline-adjusted i) plasma fluoride concentration was 9.6(6.3), 11.4(6.3), 15.6(7.7) and 14.9(10.0) ng/ml; ii) rate of urinary fluoride excretion over 0–8 h was 46(15), 44(22), 34(17) and 36(17) μg/h; and iii) rate of fluoride renal clearance was 26.5(9.0), 27.2(30.4), 13.1(20.4) and 18.3(34.9) ml/min. The observed trend of a rise in plasma fluoride concentration and decline in rate of fluoride renal clearance with increasing exercise intensity needs to be investigated in a larger trial. This study, which provides the first data on the effect of exercise with different intensities on fluoride metabolism in humans, informs sample size planning for any subsequent definitive trial, by providing a robust estimate of the variability of the effect.

Competence in fundamental movement skills is essential to enable children to be physically active. We investigated the effect of an integrated fundamental movement skill with a strength training intervention on children’s fundamental movement skills. Seventy-two (53% female) 10- to 11-year-old children from three primary schools assented to take part in this study (87% compliance). Schools were randomly allocated to a control (no intervention; n = 21), fundamental movement skill (FMS) (n = 18) or FMS and strength (FMS+; n = 20) group. Interventions were delivered twice weekly for four weeks, in addition to normal physical education. FMS competence was measured through the Canadian agility and movement skills assessment (CAMSA) (product-process) and through countermovement jump (CMJ) and 40-m sprint tests (product). Improvements were observed in the CAMSA in both FMS (4.6, 95% confidence intervals 2.9 to 6.4 Arbitrary Units (AUs), second-generation p-value (pδ) = 0.03) and FMS+ (3.9, 2.1 to 5.3 AU, pδ = 0.28) with no difference beyond our minimum threshold of 3 AU observed between these intervention groups (pδ = 1). Clear improvements in CMJ were observed in FMS+ relative to the control (25, 18 to 32%, pδ = 0) and FMS groups (15, 6.1 to 24%, pδ = 0). These preliminary data suggest combined FMS and strength training warrants further investigation as a tool to develop fundamental movement skills in children.

The school playground can promote PA for large numbers of children. This study identifies areas of the playground that children visited at break-times, the decisions according to gender and the influence of contextual and environmental variables on PA levels. The playground of a culturally diverse primary school was observed during morning break-times and lunchtimes. Counts of sedentary, LPA, and MVPA episodes, and the contexts in which they occurred were recorded using the system for observing play and leisure in youth (SOPLAY). Ball sports areas had higher counts of boys (mean ± SD; 9.9 ± 4.8) compared to girls (2.0 ± 3.5); areas promoting climbing and social interaction had higher counts of girls (7.9 ± 7.2) compared to boys (3.5 ± 2.9). The proportion of MVPA episodes during break-times was 34% ± 26%. Areas of the playground with organised activities had 2.70 (95%CI: 1.87 to 3.91) times higher MVPA counts than areas "not organised". Areas with "supervision" were associated with higher MVPA counts (1.34; 1.18 to 1.53) compared with "not supervised" areas. Organisation and supervision might influence PA choices and PA levels of children in the primary school playground. Further investigation is required to explore different playgrounds settings, and context and gender preferences.