Sleep disorders and starting time to school impair balance in 5-year-old children

To verify if sleep disorders and different starting time to school have impaired motor skills in 5-year-old children. Cross-sectional design consisting of 132 children with sleep disorders and 136 normal controls of the public school in the city of São Paulo. The group with sleep disorders was identified based on a questionnaire, and motor tests for global motor coordination, fine motor coordination, perceptual-motor coordination, and static and dynamic balance were applied in all children. In the static balance test, more specifically in the sharpened Romberg (Tandem) test, 34% of boys from the study group, who studied in the morning, failed the test (p < 0.05). In the single leg stance test, 62% of boys from the study group who studied in the morning failed (p < 0.05). This study suggests that sleep disorders may interact with the school period and alter motor performance, especially in boys studying in the morning.