An evaluation of influences on preadolescent boys' body mass index and body composition

This study was designed to investigate the differences in the diets, activity levels, body concerns, body esteem, and body perceptions of fifty preadolescent boys (ages 8–10) in relation to their body mass index (BMI; kg/m2) and their percent body fat (PBF), measured using air-displacement plethysmography. Additionally, it was designed to examine general parenting and child feeding practices of parents in relation to their sons' BMI and PBF. Boys were recruited based on their BMI and were placed into either an average BMI group (BMI percentile between the 33rd and the 68th) or a high BMI group (BMI percentile ≥ 85 th). Additionally, they were placed into either a lower PBF group (PBF < 21.8) or an upper PBF group (PBF > 21.8). The relationship between the BMI and PBF of the boys was examined, along with whether boys grouped by their BMI status would be grouped similarly based on their PBF. PBF was significantly correlated with BMI (r = 0.74, p < .0001) and the two ways of grouping boys were not independent (χ2 = 13.52, p < .0001). Twelve of the 50 boys were classified differently into the BMI and PBF groups. Results were mainly presented based on boys' BMI groups. No differences were found in the energy intakes or activity levels by boys' BMI groups. Boys in the high BMI group perceived themselves to be heavier than boys in the average BMI group, and they were more concerned about their bodies compared to boys in the average BMI group. Mothers and fathers of boys with a high BMI saw their sons as more overweight, were more concerned about their sons' weight, and used pressure to eat less often with their sons compared to mothers and fathers of boys with an average BMI. In addition, fathers of boys with a high BMI monitored their sons' eating less often than fathers of boys with an average BMI. When compared to fathers, mothers were more responsible for providing food to their sons. No differences were found in general parenting practices by boys' BMI. However, mothers were more likely to use the authoritative style of parenting compared to fathers.