A Systematic Literature Review with Meta-Analyses of Within- and Between-Day Differences in Objectively Measured Physical Activity in School-Aged Children

Abstract

BackgroundTargeting specific time periods of the day or week may enhance physical activity (PA) interventions in youth. The most prudent time segments to target are currently unclear.ObjectivesTo systematically review the literature describing differences in young people’s objectively measured PA on weekdays vs. weekends, in school vs. out of school, weekends vs. out of school and lesson time vs. break time.MethodsElectronic databases were searched for English-language, cross-sectional studies of school-aged children (4–18 years) reporting time-segment-specific accelerometer-measured PA from 01/1990 to 01/2013. We meta-analysed standardised mean differences (SMD) between time segments for mean accelerometer counts per minute (TPA) and minutes in moderate-to-vigorous PA (MVPA). SMD is reported in units of standard deviation; 0.2, 0.5 and 0.8 represent small, moderate and large effects. Heterogeneity was explored using meta-regression (potential effect modifiers: age, sex and study setting).ResultsOf the 54 included studies, 37 were eligible for meta-analyses. Children were more active on weekdays than weekends [pooled SMD (95 % CI) TPA 0.14 (0.08; 0.20), MVPA 0.42 (0.35; 0.49)]. On school days, TPA was lower in school than out of school; however, marginally more MVPA was accumulated in school [TPA −0.24 (−0.40; −0.08), MVPA 0.17 (−0.03; 0.38)]. TPA was slightly lower on weekends than out of school on school days, but a greater absolute volume of MVPA was performed on weekends [TPA −0.10 (−0.19; −0.01), MVPA 1.02 (0.82; 1.23)]. Heterogeneity between studies was high (I2 73.3–96.3 %), with 20.3–53.1 % of variance between studies attributable to potential moderating factors.ConclusionsSchool-aged children are more active on weekdays than weekend days. The outcome measure influences the conclusions for other comparisons. Findings support the tailoring of intervention strategies to specific time periods.Electronic supplementary materialThe online version of this article (doi:10.1007/s40279-014-0215-5) contains supplementary material, which is available to authorized users.

Middle School Students’ Free-living Physical Activity on Physical Education Days, Non-physical Education Days, and Weekends

“…It seems that in school even when PE is not held, students receive significantly more activity than when they are at home on weekends. This result is in line with a recent meta-analysis of 37 accelerometer studies looking at youth PA that also suggested students are more active during weekdays than weekends (Brooke, Corder, Atkin, & van Sluijs, 2014). Data from this study brings to light important information on weekend habits of students and increases the importance of physical educators promoting lifetime wellness that carries over to out-of-school time, as a recent review noted that "school physical education probably has the greatest reach" (Sallis, Carlson, & Mignano, 2012: 504) on PA levels of students.…”

Moderate-to-Vigorous Physical Activity Levels in Physical Education, School Recess, and After-School Time: Influence of Gender, Age, and Weight Status

“…These results are in line with previous studies in relation to the importance of this period to the daily recommendations of MVPA, as demonstrated the systematic review carried out by Brooke et al 38 Nevertheless, the comparison between studies is complex due to the definition of the AS period, which has been considered in many ranges of hours (eg, from 16:00 to 18:00 h 26 or from 15:30 to 20:30 h). 39 The current study has defined the AS period as "the rest of the day" or extracurricular time (from the finalization of the school schedule until the end of the day) for the analysis of the data, which impacts the total quantity of MVPA obtained.…”

Accelerometry-Derived Physical Activity Correlations Between Parents and Their Fourth-Grade Child Are Specific to Time of Day and Activity Level

“…Several studies have noted the importance of the school day for PA accumulation among elementary-aged children, with students accumulating significantly greater MVPA during the school day compared with time spent at home and children participating in significantly greater sedentary time at home compared with time spent in school. [32][33][34] In addition, children encouraged to be physically active in school have been shown to be more active outside of school compared with children whose school-day PA was restricted, and other studies have shown children to be more active during the school week compared with weekend days. [35][36][37] These findings, in concert with the weak correlation between parent-child PA levels, corroborate the importance of school-day PA.…”