Development of physical fitness in children with intellectual disabilities

BackgroundFew studies examined the development of physical fitness in children and youth with intellectual disabilities (ID), but the developmental patterns of physical fitness are largely unknown. The first aim was to examine physical fitness of primary school children with ID, aged 8-12, and compare the results with typically developing children in order to determine the performance level of children with ID. The second aim was to investigate the developmental trajectory of physical fitness in children with ID and the possible influence of gender and severity of cognitive impairment in a 4-year during longitudinal study. MethodSeventy-three children with borderline or mild ID (51 boys, 22 girls; age range 8-11 in the year of enrolment) were measured annually on running speed, aerobic endurance (cardiovascular endurance), explosive strength, handgrip strength and trunk strength. Physical fitness scores of 515 typically developing children (266 boys, 249 girls; age range 8-12) were collected for reference values. ResultsThe results indicated statistically significant differences (with moderate to large Effect Sizes) between children with ID and typically developing children in all ages, favouring the typically developing children, and showed that the gap remained stable across the ages or decreased with increasing age. Multilevel models showed that the children with ID developed statistically significant on all items of physical fitness between age 8 and age 12. There was no statistically significant effect of gender on physical fitness, and the developmental trajectories were similar for boys and girls. For children with borderline and mild ID the developmental trajectories were parallel, but children with mild ID scored statistically significant worse on running speed, explosive strength and handgrip strength. ConclusionsDespite statistically significant development of physical fitness in children with ID, their physical fitness levels should be stimulated. This should start already in young children (<8 years) and the children with the most severe cognitive impairments need special attention.