In 2003, a cross-sectional prevalence study was ušed to detect tne incidence of defective body posture in a representative sample of 3250 children aged 7,11 and 15 years in 10 towns of the Czech Republic. Differences in the incidence of defective body posture were found particularly between ages 7 and 11 (33.0 % and 40.8 %; p<0.001). Between ages 11 and 15 these differences were insignificant (40.8 % and 40.6 %; p=0.944). In total, paediatricians in 38.3 % of examined children, particularly boys, diagnosed defective body postu¬re. The most frequent defects comprised protruding shoulder blades (50 % of all children), increased lum-bar lordosis (32 %) and rounded back (31 %). Incidence of defective body posture was significantly higher in children suffering from pathological frontal curvature of the spině (p<0.001), rounded back (p<0.001) and increased lumbar lordosis (p<0.001). Children with defective body posture reported more frequent pain (at least lx a month) in the head, upper vertebrae, and lower back. Scoliosis was diagnosed in 5.8 % of examined children. Prevalence increased significantly with age and the highest incidence and number of new cases was detected amongst the 15 year-olds. The group included 14 % of children with high BMI (exceeding the 90th percentile); these children had a lower incidence of defective body posture (p= 0.045) and scoliosis (p=0.004). Zero sports activity was reported by 18.9 % of children, who had an increased likelihood of defective body posture in comparison to children participating in sports at least lx weekly (p<0.001). On average, the child¬ren spent 4 hours per week engaged in sports and 14 hours per week watching TV, video, and playing com-puter games.

        Key words: body posture - scoliosis - pain - BMI - children