Dynamic analysis of the students' physical growth differences between North and South in China

Objective To study the level of physical growth and physical development trends in north and south adolescents,so as to provide reliable information and guidance for the primary and secondary schools where carrying out the health care work.Methods By using weighted mean methods,data of the National Students physique Survey Published in 2005 were merged,according to 1985 the National Students physique Survey provinces that firstly identified 14 northern provinces and 14 southern provinces.Results During 1985 to 2005,the growth levels of the northern students in height,weight and chest circumference was better than the south(P0.05 or P0.01).In the past 20 years,the gap of height between the north and south students reduced 0.08 cm(urban boys),0.12 cm(urban girls),0.63 cm(rural male) and 0.80 cm(rural girls),gap of the weight expanded 1.07 kg(urban boys),0.51 kg(urban girls),0.69 kg(rural boys) and 0.22 kg(rural girls),gap of the chest circumference expanded 0.24 cm(urban boys),0.55 cm(rural boys) and 0.43 cm(rural girls).Conclusion The national student physical growth trend presents north better and south worse,the North-South height gap reduced,but weight and chest gap is widening.