Physical activity and determinants of physical activity in obese and non-obese children.
OBJECTIVE
To compare the physical activity (PA) patterns and the hypothesized psychosocial and environmental determinants of PA in an ethnically diverse sample of obese and non-obese middle school children.


METHODS
Cross-sectional study.


METHODS
One-hundred and thirty-three non-obese and 54 obese sixth grade children (mean age of 11.4+/-0.6). Obesity status determined using the age-, race- and gender-specific 95th percentile for BMI from NHANES-1.


METHODS
Objective measurements were collected of PA over a 7-day period using the CSA 7164 accelerometer: total daily counts; daily moderate (3-5.9 METs) physical activity (MPA); daily vigorous physical activity (> or =6 METs; VPA); and weekly number of 5, 10 and 20 min bouts of moderate-to-vigorous physical activity (> or =3 METs, MVPA). Self-report measures were collected of PA self-efficacy; social influences regarding PA, beliefs about PA outcomes; perceived PA levels of parents and peers, access to sporting and/or fitness equipment at home, involvement in community-based PA organizations; participation in community sports 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 well as significantly fewer 5, 10 and 20 min bouts of MVPA. Obese children reported significantly lower levels of PA self-efficacy, were involved in significantly fewer community organizations promoting PA and were significantly less likely to report their father or male guardian as physically active.


CONCLUSIONS
The results are consistent with the hypothesis that physical inactivity is an important contributing factor in the maintenance of childhood obesity. Interventions to promote PA in obese children should endeavor to boost self-efficacy perceptions regarding exercise, increase awareness of, and access to, community PA outlets, and increase parental modeling of PA.
Trost
S G
SG
School of Human Movement Studies, The University of Queensland, Brisbane, Queensland 4072, Australia. strost@hms.uq.edu.au
Kerr
L M
LM
Ward
D S
DS
Pate
R R
RR
D001315:Australia; D015992:Body Mass Index; D002648:Child; D003430:Cross-Sectional Studies; D015444:Exercise / Q000523:psychology; D005260:Female; D015438:Health Behavior; D006801:Humans; D008297:Male; D009749:Nutrition Surveys; D009765:Obesity / Q000209:etiology*; D010290:Parents / Q000523:psychology; D010809:Physical Fitness; D020377:Self Efficacy; D012931:Social Environment; D013997:Time Factors