Longitudinal Study On The Physical Development Of Daur Children And Adolescents In Hulun Buir City In Inner Mongolian

Nowadays, data about the physical growth of children and adolescents has been accumulated. As one of the less populated nationality, Daur was not included in the previous national students physical and health investigation and monitoring because of the population was less than 10 millions in the third census in 1982. The studies about Daur children and adolescents physical development were less, and the existed materials could not clearly reflect contemporary Daur children and adolescent physical development status and tendency. Therefore,17 physical characteristics and 16 indexes were measured in 1980 effective Daur samples (970 boys and 1010 girls) in June 2012. The students were 6～18 years old from the Daur primary and middle school in Hulun Buir city of Morin Dawa flag from Inner Mongolia.The indexes including body weight, height and breadth, girths of some portion in the body, skinfold thicknesses, somatotype and nutritional status were analyzed to reveal the status and tendency of Daur children and adolescents physical development, and the differences between urban and rural Daur children’s physical development. The somatotype relationship between Daur nationality and other ethnic students were analyzed using cluster analysis method. The characteristics of longitudinal changes of Daur students’physical development for more than 20 years were studied.The results were as follows:(1) Most physical indexes were increased with age in Daur boys and girls, but the growth rate and the variation scope of each age group were different in both boys and girls, which most of growth curves in boys and girls were double intersected. Sexual difference was remarkable among most of the age groups, the rapid growth period of boys were from 10 to 12 years old while the girls’ were from 9 to 10 years old. Compared with other ethnic groups, the development of Daur students’ height and weight was at upper middle level; (2) The limbs subcutaneous fat development were better than that of the hindquarters cadres subcutaneous fat development of Daur students in boys and girls, most skin-fold thickness values and body fat content of girls were higher than that of the same age boys, but the lean body mass of the boys were higher than girls. Compared with other ethnic groups, the development of triceps skinfold thickness and subscapular skinfold thickness in boys and girls were at upper middle level; (3) There were gender differences in each of body circumference at few age groups, which characterized they were higher in boys. Compared with other ethnic groups, the girth of chest growth of the students was at upper middle level; (4) Increasing with age, the somatotype of girls changed obviously. For boys, the main somatotype was mesomorphy category; for girls, it changed from mesomorphy category to ectomorph-endomorph, and finally to the mesomorphic endomorph after 12 years old. The cluster analysis showed that the somatotypes of the boys were similar to the Han nationality in Inner Mongolia, and the girls were similar to the Mongolia nationality in Inner Mongolia; (5) The rate of malnutrition (Male 2.27%, Female 1.29%) was lower, the rate of overweight (Male 4.47%, Female 8.02%) and obesity (Male 19.69%, Female 17.38%) were relatively higher, it indicated that the overnutrition problem of Daur students was not optimistic; (6) The majority of anthropometric indexes of 7-12 year-old Daur Children showed some differences between urban and rural areas, which were higher in the urban areas than that of the rural ones (P<0.01); (7) For over 20 years, the physical development level of Daur students was overall upward trend especially in height, weight, chest circumference index. The degree of body full in boys and girls were increased, but the development of chest was not ideal, and the breadth of shoulder and pelvis width even declined at some higher age groups. Compared with the past, nutritional status were improved while overweight and prevalence of obesity increased significantly.In this paper, we made a longitudinal study on the physical development of children and adolescents from Hulun Buir City in Inner Mongolia. Based on the detailed analysis of the current situation and development of the physical, we compared the results with 22 years ago. The results can provide the latest information for the physical development of Daur children and adolescents, and can also understand the present situation of the physical development in Inner Mongolia Daur children and adolescents, the changes of the past 20 years and trend. It would be helpful to promote their physical health.