title: Characteristics associated with physical activity among independently ambulant children and adolescents with unilateral cerebral palsy.
abstract: OBJECTIVE
  This study aimed to quantify the contribution of physical, personal and environmental characteristics to physical activity among independently ambulant children with unilateral cerebral palsy (CP).
  
  
  METHODS
  One-hundred and two children with unilateral CP (52 males, 50 females; 52 right hemiplegia; mean age 11y 3mo, range 8-17y [SD 2y 4mo]) classified at Gross Motor Function Classification System (GMFCS) levels I = 44 and II = 58 participated. Physical activity was measured over 4 days using ActiGraph accelerometers recording as activity counts. GMFCS, functional strength, 6-minute walk test (6MWT), mobility limitations (MobQues28), age, sex, Assessment of Life-Habits recreation domain, Participation and Environment Measure for Children and Youth (PEM-CY) and environmental characteristics were considered for selection in a linear regression model. These served as independent variables which were determined using a backwards selection procedure.
  
  
  RESULTS
  Younger age, male sex, increased performance on the 6MWT, and increased participation in the home and community measured using the PEM-CY were significantly associated with activity counts (p<0.001). However, the model fit was somewhat weak (R(2) =0.32), indicating that much of the variation was unexplained. Older age and reduced community participation were associated with high inactivity (p<0.001).
  
  
  CONCLUSIONS
  Physical activity interventions should primarily target adolescents and females. Walking endurance and participation in the home and community may represent modifiable characteristics to increase physical activity.
authors.affiliation: Queensland Cerebral Palsy and Rehabilitation Research Centre, The University of Queensland, Herston, Qld, Australia.
authors.forename: Louise E
authors.initials: LE
authors.lastname: Mitchell
authors.forename: Jenny
authors.initials: J
authors.lastname: Ziviani
authors.forename: Roslyn N
authors.initials: RN
authors.lastname: Boyd
mesh_terms: D061725:Accelerometry; D000293:Adolescent; D000367:Age Factors; D001315:Australia; D002547:Cerebral Palsy / Q000503:physiopathology* / Q000523:psychology*; D002648:Child; D003430:Cross-Sectional Studies; D004185:Disability Evaluation; D005080:Exercise Test; D005260:Female; D007839:Functional Laterality; D006801:Humans; D016014:Linear Models; D008297:Male; D009043:Motor Activity; D053580:Muscle Strength; D012737:Sex Factors; D012919:Social Behavior; D012959:Socioeconomic Factors; D016138:Walking