The Comparison Research On The Body Fat Percentage Measurement And Assessment Methods For The Adolescent

The adolescent age is crucial for the growth of young people.During this period,the percentage and distribution of body fat and fat free mass change a lot,which are the two important parts of body composition. Through accurate measurement and assessment of the body fat percentage, we can get to know the physical condition of the adolescent,It's very important to build up and verify a way for the young people to assess and measure the body fat percentage,and this is a remarkable topic in the body composition assessment research area.There are a lot of methods to measure or assess the body fat mass and percentage,and each method has its own applicable scopes and its own limitations.This research aims to compare the results of three different ways which are skin fold fat thickness,bioelectric impedance analysis and dual energy X-ray absorptiometry.Also,it's the goal of this thesis to build up a formula to assess the body fat percentage of the adolescent with the skin folds,providing theory and practical support to the body fat assessment research for the young people.In this research we selected 131 students from the first and second grades of Beijing No.27 middle school.These samples consist of 66 boys and 65 girls,and they are grouped by the skeletal ages.We measured the skin folds at eight different positions for each people,and also measured the body fat percentage through BIA and DEXA,in order to get to know the growth and distribution of their body fat.By comparing the results from these three different ways,we have below conclusions.1.The body weight and other parameters of body composition become larger with the growth of the young people between 13 and 16 years old.The boys' body weight increase significantly,while the girls' weight increase steadily,however,the different body compoditions have inconsistent changes.The body fat of both the boys and girls increase steadily;the muscle content grows a lot during this period on boys,but not so much for girls.The bone mineral content change a lot on both boys and girls.2.The body fat percentage doesn't change a lot on boys but increase a lot on girls between 13 and 16 years old.The body fat percentage difference between boys and girls become larger with the growth.3.It turns out to be feasible to assess the body fat percentage through skin folds or BIA methods,but the results are not very accurate.4.Through this research a reliable and accurate formula comes out to assess the adolescent's body fat percentage with skin folds.The formula is as below.Boys:Fat%=12.824+0.444*Breast+0.241*SubscapularGirls:Fat%=19.655+0.315*Triceps+0.202*Subscapular...