Physical activity and body mass index of school children and adolescents in Abeokuta, Southwest Nigeria.

BACKGROUND Physical inactivity and sedentary lifestyles are known to predispose to overweight and obesity. These lifestyles are also known to track from childhood into adulthood with consequent cardiovascular and metabolic problems. This study aimed to describe the frequency of physical activity and the relationship between physical activity and body mass index of urban Nigerian school children and adolescents. METHODS Children from seven schools in Abeokuta, southwest Nigeria were selected using a multi-staged random sampling technique. RESULTS Of 570 children, 411 (72.1%) were involved in moderate to vigorous physical activities. Involvement in physical activity was higher in older children (P<0.001), males (P<0.001), and children of mothers with a higher educational level (P=0.03). Eleven (1.9%) children were overweight or obese whereas 163 (28.6%) were underweight. There were more children with underweight than overweight among the subject population with a high level of physical activity (35.6% vs. 4.4%, P=0.499). CONCLUSIONS A large proportion of the children in urban Nigeria participate in physical activity. The prevalence of overweight and obesity is low but undernutrition is a major nutritional problem among these children.