Study On The Bone Density And Body Composition Of College Students And Their Correlation With Athletic Qualit

Objectives:This study aimed to analyze the current situation of Body Mineral Density（BMD）and Body Composition（BC）of college students,discuss their relationship with athletic fitness of college students and clarify the key factors dominating their BMD and BC.Methods:A total of 504 college students in Shandong province were used as samplers including 278males and 226 females.OSTEO pro and Inbody analyzer were used to measure BMD and BC respectively.Their athletic fitness was measured according to the"National Standard of Students’physical health".In statistical analysis,all samplers were classified into different groups according to their osteoporosis index（OI）so as to determine the number and proportion of them.Then,one-way ANOVA was used to observe the difference in characteristic index and athletic fitness parameters between or among the groups.Tamhane’s T2（M）test was used if the variance was uneven.The correlation between the variables of BMD,BC and athletic fitness were analyzed by Pearson correlation analysis.Finally,Multiple Stepwise Regression was conducted to observe the prediction of the variables of athletic fitness to BC,the proportion of fatness and muscles.P<0.05 indicates the standard of significant difference,and P<0.01indicates a very significant standard for difference.All data were processed by SPSS 19.0.Results:1.The incidence of low bone mass in male and female college students was 24.10%and27.88%,respectively.The incidence of osteoporosis was 10.79%and 3.10%,respectively.The rates of body fat obesity in male and female college students were 14.75%and 29.65%,and the rates of low body fat were 30.21%and 13.27%,respectively.The differences of body fat content and proportion in normal,obese and low body fat groups were significant.The incidence of low muscle mass in male and female college students was 15.83%and 37.17%,respectively.The characteristic values of BMD and BC were significantly different between or among the groups.2.For the college students,the performance of 50m,1000m and pull-up in the normal group was significantly better than those with low bone and osteoporosis for the males.The performance of 50m were significantly better than those with osteoporosis group for the females,P<0.05.The performance of 50m,1000m,standing long jump and pull-up in normal group was significantly better than that in obese group,and lower than that in low body fat group for the males,P<0.05;The performance of 50m,800m,standing long jump and sit-up in the normal group was significantly better than those in the obese group,and worse than those in the low body fat group（except for standing long jump）for the females,P<0.05;The performance of 50m,1000m（800m）,standing long jump,pull-forward（sit-up）and sitting forward in normal group was better than those with low muscle mass for females,P<0.05.3.The scores of 50m（male and female）,1000m,pull-up and sit-up were correlated with OI,T value,Z value and SOS,P<0.05;Results of 50m（male and female）,1000m（800m）,standing long jump（male and female）,pull-up and sit-up were significantly negatively correlated with body fat and body fat percentage（P<0.05）.Scores of 50m（male and female）,1000m（800m）,standing long jump（male）and pull-up were significantly positively correlated with TSM/Wt（%）,P<0.05.4.Stepwise regression standardized Equation.For males:Bone index=0.166x _pull-up-0.121x_50m,fat content ratio=0.314x_50m+0.280x_1000m-0.145x _{long jump}-0.114x _pull-up,Body fat ratio=-0.277x_1000m-0.236x_50m+0.203x _pull-up+0.139x _{long jump};Female college students:bone index=0.178x _sit-up,fat ratio=0.321x_800m-0.263x _{long jump},muscle ratio=-0.338x_800m+0.011xlong jump.Conclusions:1.College students shows higher incidence in osteopenia and osteoporosis,high and low body fat,and low muscle mass and there were significant differences in the index characteristic values between or among the groups.2.The incidence of osteopenia and osteoporosis in male college students is higher than that in female.The incidence of high fatness and low muscle mass in female college students is higher than that in males.3.Whether male or female,students with low bone and osteoporosis,high body fat and low muscle had lower level of athletic fitness,but there were differences in athletic fitness among different groups.4.The variables of bone mass,body fat and muscle is closely related to most indicators of athletic fitness,and there are sex difference.5.According to the degree of influence of athletic fitness,upper body strength and speed are the related factors with bone mass in the males,while trunk strength are the related factors with bone mass in the females.Speed,endurance,lower extremity and upper extremity strength were the key correlation factors with body fat/body weight ratio in the males,while endurance and lower extremity strength were the key correlation factors with body fat/body weight ratio in the females.Endurance,speed,upper and lower limb strength are the correlation factors that affect the muscle/body weight ratio of the males,while endurance and lower limb strength are the correlation factors that affect the muscle/body weight ratio of the females.These are the key factors and sensitive indicators to determine and predict the bone mass,body fat and muscle ratio of college students,respectively.