MVPA is associated with lower weight gain in 8-10 year old children: a prospective study with 1 year follow-up

Abstract

Background: Studies relating physical activity (PA) to weight gain in children have produced mixed results, although there is some evidence for stronger associations with more intense physical activities. The present study tested the hypothesis that weight gain over one year in 8-10 year olds would be more strongly predicted by moderate and vigorous physical activity (MVPA) than total physical activity (total PA) or sedentary behaviour.

Methodology: Participants were 280 children taking part in the Physical Exercise and Appetite in Children Study (PEACHES). Weight status was assessed using body mass index (BMI), fat mass index (FMI), and waist circumference (WC) in school Year 4 (baseline; age 8.7 yrs) and Year 5 (follow-up; age 9.7 yrs). Physical activity was measured at baseline using the Actigraph GT1M accelerometer to assess total PA (mean accelerometers counts per minute), MVPA; ≥ 4000 counts per minute) and sedentary time (<100 counts per minute).

Principal findings: After adjustment for baseline BMI, SES, sex and ethnicity, MVPA was significantly associated with follow-up BMI (adjusted β = -0.07; p = 0.002). This association was independent of total PA or sedentary time. Similar results were observed for FMI; again MVPA was significantly associated with follow up FMI (β = -0.16; p = 0.001) independent of total PA or sedentary time. The pattern was similar for WC (β = -0.07), but the association between MVPA and WC did not reach significance at p = 0.06.

Conclusion: The results of this study strongly support promotion of MVPA in children.

Figure 1. Flow of participants through the PEACHES physical activity study.

There were no significant differences in sociodemographic data between those who provided full valid data at both time points and those who did not (p's all >0.05).

Figure 2. Adiposity by tertile of moderate and vigorous physical activity (MVPA; >4000 accelerometer counts per minute).

Participants were 8–10 year old children participating in the PEACHES study. Data were mean change (follow-up minus baseline scores) adjusting for gender, SES, ethnicity, total physical activity and sedentary behaviour. Figure 2A displays 1 year change in body mass index (BMI; weight in kg/height in m²; n = 280 children). 2B 1 year change in fat mass index (FMI; fat mass/height in m²;n = 279 children) and 2C 1 year change in waist circumference (WC; n = 280 children). All linear trends were significant at p<0.01. Between group differences are highlighted; ** = p<0.01.