title: Psychosocial correlates of physical activity in healthy children.
abstract: BACKGROUND
  Understanding the determinants of physical activity in children is critical for the treatment and prevention of childhood obesity. Social-cognitive theory has been used to understand behavioral patterns in children.
  
  
  OBJECTIVE
  To explore the relationship between health beliefs, self-efficacy, social support, and sedentary activities and physical activity levels in children and to examine the relationship between physical activity and children's self-esteem.
  
  
  METHODS
  Ninety-two children aged 10 to 16 years completed the study. Physical activity was monitored for 1 week with a motion detector (Actitrac; IM Systems, Baltimore, Md). Moderate-level activity and high-level activity were defined based on the results of treadmill testing. Health beliefs, self-efficacy, social influences, and time spent in sedentary behaviors were determined through questionnaires. Self-esteem was measured using the Piers-Harris Children's Self-Concept Scale. Chronic anxiety was measured with the Revised Children's Manifest Anxiety Scale.
  
  
  RESULTS
  There was a significant decline in physical activity levels between ages 10 and 16 years, particularly in girls. Preteen girls spent approximately 35% more time in low- and high-level activity than did teenage girls (P<.001). Overall, children spent 75.5% of the day inactive, with a mean +/- SD of 5.2 +/- 1.8 hours watching television, sitting at the computer, and doing homework. In contrast, only 1.4% of the day (12.6 +/- 12.2 minutes) was spent in vigorous activity. Time spent in sedentary behaviors was inversely correlated with the amount of moderate-level activity (P<.001) but not high-level activity. In contrast, time spent in high-level activity correlated with self-efficacy scores (P<.001) and social influences scores (P<.005). High-level physical activity was also associated with improved self-esteem (P<.05). Higher health beliefs scores were not correlated with physical activity levels.
  
  
  CONCLUSIONS
  Children and adolescents are largely sedentary. Correlates of high- and low-level physical activity are different. Time spent on sedentary activities is inversely correlated with moderate-level activity, while self-efficacy and social influences are positively correlated with more intense physical activity. In addition, increased high-level physical activity is an important component in the development of self-esteem in children.
authors.affiliation: Childhood Weight Control Program, Division of Pediatric Gastroenterology & Nutrition, Robert Wood Johnson Medical School/UMDNJ, One Robert Wood Johnson Place, New Brunswick, NJ 08903-0019. strausrs@rwja.umdnj.edu
authors.forename: R S
authors.initials: RS
authors.lastname: Strauss
authors.forename: D
authors.initials: D
authors.lastname: Rodzilsky
authors.forename: G
authors.initials: G
authors.lastname: Burack
authors.forename: M
authors.initials: M
authors.lastname: Colin
mesh_terms: D000293:Adolescent; D017677:Age Distribution; D000704:Analysis of Variance; D001007:Anxiety / Q000175:diagnosis* / Q000453:epidemiology; D001294:Attitude to Health; D002648:Child; D015444:Exercise / Q000523:psychology*; D005260:Female; D006801:Humans; D008019:Life Style; D008297:Male; D009515:New Jersey; D011336:Probability; D011584:Psychology; D012016:Reference Values; D012044:Regression Analysis; D018570:Risk Assessment; D012494:Sampling Studies; D012649:Self Concept; D017678:Sex Distribution; D011795:Surveys and Questionnaires