Influence Of Low Bmi On Acute Physical Activity Benefits On Cognition In Children

PURPOSE: Physical inactivity has become increasingly prevalent during childhood, with >50% not meeting the recommended 60 min of daily moderate-to-vigorous physical activity (PA). Prior research has suggested that exercise benefits cognition in normal weight (NW) children, but recent research has shown that children with obesity may not experience the same cognitive benefits following acute PA. Given the contrasting cognitive effects of exercise among different weight statuses, there remains a gap in the literature regarding the extent to which low BMI influences acute PA benefits on cognition in childhood. Accordingly, the aim of this pilot investigation was to examine the relationship between a single dose of acute PA in UW children on cognitive performance. METHODS: Performance on a flanker task following two randomized and counterbalanced 20-minute interventions: acute PA (treadmill walking at ~65% HRmax) and seated rest (control) on separate days was compared between matched samples of 14 UW children (50% females, 9.97 ± 0.20 years old) and 70 NW children (50% female, 9.95 ± 0.08 years old). UW and NW children did not differ on demographic measures of age, sex, intelligence quotient, socioeconomic status, and aerobic fitness (all p’s > 0.13). RESULTS: Consistent with prior investigations, children were more accurate following the acute PA (91.97 ± 0.85%) compared to following seated rest (88.26 ± 1.19%) (F(1, 82) = 18.96, p ≤ 0.001, ɳ2 = 0.19). Importantly, there were no differences in performance based on weight status, suggesting the acute PA is cognitively beneficial for both NW and UW children (PA: 90.77 ± 1.55%; CON: 86.40 ± 2.17%). There were no effects of weight status or intervention for reaction time. CONCLUSIONS: Findings suggest that cognitive performance is higher following acute PA compared to rest, and acute PA is beneficial to UW children. Similar to NW children, UW children experience cognitive benefits following acute PA. Future studies should continue to investigate responses to PA in UW children. Findings from this investigation support public health guidelines for PA to promote cognitive performance across the school day.