Age-related anthropometric changes in physical development among aboriginal schoolchildren in Russia’s North-East

Abstract

Purpose This study assessed anthropometric changes developed by schoolchildren from the indigenous population of the Magadan Region in the age aspect. Materials and Methods Two hundred and eight boys and one hundred and ninety girls from the native indigenous nations (Evens, Koryaks, Itelmen) participated in the 2021-2023 Anthropometric Survey. They accounted for 67.2% of all schoolchildren surveyed (592 people in total). According to generally accepted research methods, the following indicators were measured: body height (BH), body mass (BM), chest circumference (CC), sitting height (HSit), right and left hand strength. To assess the subjective physical development, we calculated annual gains in weight and height indices, as well as proportional physique and its strength. Results In the age dynamics from 8 to 17 years, we could see a natural increase in the absolute body indicators of BH, BM, HSit, CC, and right and left hand strength. The rate of annual growth indicated different timing of the periods of pronounced gains in the body parameters. Girls exhibited a CC maximum increase at 10-11 years old with simultaneously raising BH, BM, HSit, and muscle strength indicators at 11-12 years old. During the same age periods, boys showed a pronounced BH growth with BM with CC gaining at 12-13 years of age. After a slight attenuation in the growth rate, we could observe a BH jump occurred at the age of 14-15, which was caused by gender aspects in older children groups. Sex-related characteristics of BH growth rates are primarily associated with differences in the body limbs (legs) growth rates during the puberty, and tend to be higher in boys. In general, rather weak physique with a predominance of asthenic somatotype was characteristic of the examined boys. A proportional body type with high percentage of those with relatively short legs was more common in the examined girls. Conclusion The results obtained have provided us with evidence on a better level of physical development and the body adaptive adjustments exhibited by girls compared to boys.