Systematic review of the relationship between habitual physical activity and motor capacity in children with cerebral palsy

Habitual physical activity (HPA) has many benefits for general health. Motor capacity in children with cerebral palsy (CP) can impact on their HPA. This study aimed to systematically review the available literature on the relationship between HPA and motor capacity in children with CP aged 3-12 years for all gross motor functional abilities (GMFCS I-V) compared to typically developing children. Five electronic databases (Pubmed, Cochrane, Embase, Cinahl and Web of Science from 1989 to November, 2013) were searched using keywords "children with cerebral palsy", "physical activity", "motor capacity" and "motor function" including their synonyms and MesH terms. Studies were included if they (i) were conducted in children with CP aged between 3 and 12 years, (ii) assessed HPA or time spent sedentary, (iii) assessed motor capacity in order to evaluate the relationship between HPA and motor capacity. All articles retrieved were reviewed by two independent reviewers and discussed until they reached consensus. Study quality of reporting was evaluated using the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) criteria. Search results identified 864 articles but after review of the title and abstract only 21 articles warranted closer consideration. Ten articles met the strict inclusion criteria as nine articles did not assess HPA and two were conference abstracts. Study quality assessment (STROBE) found nine articles were good quality (≥60%) and one was poor quality (55.9%). Participants were mean age 8.4 (SD=2.1) years (range 2-17 years) and included children at all GMFCS levels (3 studies), while seven studies only recruited GMFCS level I-III. HPA measurements were either subjective (Activity Scale for Kids, Dutch Questionnaire of Participation in physical activity and assessment of participation in physical education at school and regular physical activity in leisure time) or objective (StepWatch® and ActiGraph®7164). Nine studies found that motor capacity was directly associated with HPA, HPA in children with CP with high functional level (GMFCS I) was higher than those with lower functional levels (GMFCS III-V); while one study reported no relationship between HPA and GMFCS level (HPA was measured by questionnaire, a potential limitation). Further studies are required to further elucidate HPA levels (active, sedentary behavior) according to objective motor capacity measures, age and gender to inform healthy lifestyle behavior (active/sedentary) in children with CP