Long-term changes in body proportions since 1983 to 2010 in children and adolescents from Kraków (Poland).

The aim of the study was to assess changes in body proportions and the rate of growth in boys and girls from the population of Kraków (Poland) in the years 1983-2010. The children and adolescents analyzed in this study were included in three cross-sectional surveys conducted in Kraków in 1983, 2000 and 2010. The sample sizes were the following: 3,214 boys and 3,250 girls in 1983, 2,381 boys and 2,096 girls in 2000, 1,889 boys and 1,989 girls in 2010. The comparison of selected features and indices were made: subischial leg length, biacromial width, biiliac width, reciprocal ponderal index, skelic index, pelvi-acromial index, shoulder-height ratio, pelvis-height ratio. To analyze the rate of growth the modeling functions of Preece-Baines (PB1) were used. Over the analyzed period, the children and adolescents from Kraków showed a positive secular trend for all the analyzed traits, especially consistent in the width of the pelvis and shoulders. The acceleration of development was reflected in the earlier pubertal spurt in the studied lengths and widths. The changes in body proportions showed a tendency to more slender body proportions in children between 3 and 8 years of age in girls and after puberty, and the relative shortening of the lower limbs. In the group of boys, there was a distinct widening of hips and pelvis, more pronounced than in height. In girls, similar changes were noted only until the period of puberty, and throughout the entire duration of ontogeny for the shoulders-height ratio.