Objectively assessed recess physical activity in girls and boys from high and low socioeconomic backgrounds.

BACKGROUND: The school environment influences children's opportunities for physical activity participation. The aim of the present study was to assess objectively measured school recess physical activity in children from high and low socioeconomic backgrounds. METHODS: Four hundred and seven children (6-11 years old) from 4 primary schools located in high socioeconomic status (high-SES) and low socioeconomic status (low-SES) areas participated in the study. Children's physical activity was measured using accelerometry during morning and afternoon recess during a 4-day school week. The percentage of time spent in light, moderate, vigorous, very high and in moderate- to very high-intensity physical activity were calculated using age-dependent cut-points. Sedentary time was defined as 100 counts per minute. RESULTS: Boys were significantly (p < 0.001) more active than girls. No difference in sedentary time between socioeconomic backgrounds was observed. The low-SES group spent significantly more time in light (p < 0.001) and very high (p < 0.05) intensity physical activity compared to the high-SES group. High-SES boys and girls spent significantly more time in moderate (p < 0.001 and p < 0.05, respectively) and vigorous (p < 0.001) physical activity than low-SES boys. CONCLUSIONS: Differences were observed in recess physical activity levels according to socioeconomic background and sex. These results indicate that recess interventions should target children in low-SES schools.

Effects of a playground marking intervention on school recess physical activity in French children.

OBJECTIVE: Playground interventions offer an opportunity to enhance school recess physical activity. We aimed to assess the effects of playground marking on objectively measured school recess physical activity in French children. METHODS: Participants were four hundred and twenty children (6-11years old) from 4 primary schools in Nord-Pas de Calais, France. Children's physical activity (PA) was measured with a uniaxial accelerometer twice a day (morning and afternoon recess) during a 4-day school week in April and May 2009. Two experimental schools (EG) received a recess-based intervention (playground markings) and two others served as controls (CG). Percentage of time spent on the following intensities of physical activity during school recess was measured before and after intervention: sedentary (SED), light physical activity (LPA), moderate physical activity (MPA), vigorous physical activity (VPA), very high physical activity (VHPA) and moderate-to-vigorous physical activity (MVPA). RESULTS: At baseline, school recess PA among children from CG was significantly (p<0.001) higher than that among EG children. No interaction was observed between the recess-based intervention and gender. After the intervention, the EG spent significantly (p<0.05) more time in MPA, VPA and MVPA with a concomitant significant decrease in SED (p<0.05) compared to baseline, while the PA in CG remained unchanged. CONCLUSION: Painted playground markings had a positive short-term effect on school recess physical activity levels.

Is there any relationship between physical activity level and patterns, and physical performance in children?

BACKGROUND: It is often assumed that physical activity (PA) and physical performance during childhood and adolescence are beneficial for health during adulthood, but a positive relationship between PA and physical performance has not been precisely clarified in children. The lack or the weakness of the relationships between PA and physical performance could be due to the measure of PA. If the use of accelerometry is considered as an objective and common measure of PA, the real patterns of children's habitual PA must be reflected. The aim of this study was to investigate the relationship between the levels and patterns of PA assessed with high frequency accelerometry and physical performance in young children. METHODS: Eighty-six boys and 101 girls aged 6-12 years participated in this study. Physical activity was measured over a 7-day period, using a 5-s epoch. Physical performance was assessed by means of EUROFIT tests (anthropometrics, standing broad jump, the 10 × 5 meter shuttle run, the sit-and-reach, the handgrip, the number of sit-ups in 30 seconds, the 20-meter shuttle run). RESULTS: No relationship was found between PA and physical performance. In boys only, body fatness was negatively associated with vigorous PA (r = -0.38, p < 0.001) and very high PA (r = -0.35, p < 0.01), in contrast to light PA (r = 0.28, p < 0.01), which was positively related to body fatness. CONCLUSION: In 6- to- 12 year- old children, the more active children were not the fittest. Our results also underline the need for uniformity in approach to measurement of PA, body composition and health-related fitness between studies.

Physical activity patterns in French youth--from childhood to adolescence--monitored with high-frequency accelerometry.

OBJECTIVES: To investigate changes in time spent in light (LPA), moderate (MPA), vigorous (VPA), very high physical activity (VHPA) from childhood to adolescence, according to age and sex, when measured with high frequency accelerometry. METHODS: Three hundred and sixty-one children, 94 preschoolers (Ps), 156 from primary schools (PS) and 111 from junior high schools (JHS)) were involved in this study. The children's physical activity was assessed with a uniaxial accelerometer over a seven-day period. The epoch duration was set at 5 s and data collected between 7 am and 9 pm. The times spent below and above different PA thresholds, corresponding from LPA (<3 METs) to VHPA (>9 METs), were calculated. RESULTS: During the week, the boys spent significantly more time in MPA to VHPA than the girls (p < 0.001). From Ps to PS, LPA remained stable, while VPA and VHPA decreased significantly (p < 0.05). From PS to JHS, time spent in LPA, VPA, and VHPA increased significantly (p < 0.05). On the contrary, MPA increased significantly (p < 0.05) between Ps and PS and decreased significantly (p < 0.05) from PS to JHS. From PS to JHS, time spent in LPA increased significantly more during free days than during school days (p < 0.05) while VPA and VHPA increased significantly (p < 0.05) more during school days than during free days. CONCLUSIONS: Moderate to very high PA decreased from childhood to adolescence. Changes in PA patterns were associated with an increase of LPA and a concomitant decrease of MPA, while changes were more pronounced during free days than during school days.