Physical activity and determinants of physical activity in obese and non-obese children

OBJECTIVE: To compare the physical activity (PA) patterns and the hypothesi zed psychosocial and environmental determinants of PA in an ethnically dive rse sample of obese and non-obese middle school children. DESIGN: Cross-sectional study. SUBJECTS: One-hundred and thirty-three non-obese and 54 obese sixth grade c hildren (mean age of 11.4 +/-0.6). Obesity status determined using the age- , race- and gender-specific 95th percentile for BMI from NHANES-1. MEASUREMENTS: Objective measurements were collected of PA over a 7-day peri od using the CSA 7164 accelerometer: total daily counts; daily moderate (3- 5.9 METs) physical activity (MPA); daily vigorous physical activity (greate r than or equal to 6 METs; VPA); and weekly number of 5, 10 and 20 min bout s of moderate-to-vigorous physical activity (greater than or equal to 3 MET s, MVPA). Self-report measures were collected of PA self-efficacy; social i nfluences regarding PA, beliefs about PA outcomes; perceived PA levels of p arents and peers, access to sporting and/or fitness equipment at home, invo lvement in community-based PA organizations; participation in community spo rts teams; and hours spent watching television or playing video games. RESULTS: Compared to their non-obese counterparts, obese children exhibited significantly lower daily accumulations of total counts, MPA and VPA as we ll as significantly fewer 5, 10 and 20 min bouts of MVPA. Obese children re ported significantly lower levels of PA self-efficacy, were involved in sig nificantly fewer community organizations promoting PA and were significantl y less likely to report their father or male guardian as physically active. CONCLUSIONS: The results are consistent with the hypothesis that physical i nactivity is an important contributing factor in the maintenance of childho od obesity. Interventions to promote PA in obese children should endeavor t o boost self-efficacy perceptions regarding exercise, increase awareness of , and access to, community PA outlets, and increase parental modeling of PA .