Cognitive-behavioural Physical Activity Treatment in African-American Pre-schoolers: Effects of Age, Sex, and BMI
Aim: Prevalence of overweight and obesity in children of 5 years and younger has greatly increased in countries including Australia, Canada, the UK and the USA, with African-Americans most affected in the USA. Low amounts of physical activity may be a primary cause. Interventions intended to increase physical activity during pre-school have had minimal effects. Methods: A physical activity intervention derived from self-efficacy and social cognitive theory administered by pre-school teachers in the USA (Start For Life) was contrasted with typical care over 8 weeks. The 30-min-per-day treatment incorporated structured gross motor skill physical activities and training in self-management and self-regulation skills. The African-American children in the treatment (n = 154, 21 classrooms) and control (n = 121, 11 classrooms) groups ranged in age from 3.5 to 5.6 years. Results: Mixed-model repeated measures analysis of variances indicated significantly (P ≤ 0.05) greater increases in moderate-to-vigorous physical activity (MVPA) and vigorous physical activity (VPA) in the treatment group when both the children and classrooms were the unit of analysis. Time in sedentary activities was not affected. Together, age, sex and body mass index (BMI) percentile significantly predicted treatment-related changes in MVPA (R2 = 0.11) and VPA (R2 = 0.11), with age (β = −0.22 and β = −0.23, respectively) and BMI percentile (β = −0.24 and β = −0.23, respectively) contributing uniquely to the explained variances indicating greater treatment effects for participants who were younger and had a lower BMI percentile. Conclusions: The Start For Life treatment was associated with increased MVPA by approximately 1 h per week, with most of that change being in VPA. After sufficient replication, adjustments may be made to maximise treatment effects.