运动在BMI影响健康相关生命质量中的中介效应

Mediating effect of exercise on the relationship between body mass index and health-related quality of life

目的探讨运动在BMI和健康相关生命质量（HRQOL）之间的中介效应。方法应用简明健康状况调查问卷SF-36量表对两所医院体检中心进行常规体检的人群1114例研究对象进行生命质量的测评，利用研究对象的主观评价对运动水平进行分级，研究变量之间的效应关系。结果HRQOL总分为（76．26＋16．10）分，生理领域得分为（75．97±16．67）分，心理领域得分为（76．55±18．33）分。相关分析表明：BMI与一般健康状况（r=0．109）、精力（r=0．116）、社会功能（r=0．092）、情感职能（r=0．122）以及生理机能（r=0．145）维度呈现正相关关系（P〈0．01），与PF（r=-0．07，P=0．019）维度呈现负相关关系。进一步的分层回归分析显示：运动在一般健康状况、精力和精神健康三个维度发挥的中介效应具有统计学意义，中介效应占总效应的百分比分别为5．84％、9．14％、6．58％。结论BMI对HRQOL的影响在部分维度是通过运动这一中介变量间接实现的，但BMI对HRQOL的影响主要还是通过直接效应实现的，并且在一定范围内对HRQOL具有保护作用。

Objective To evaluate the effect of exercise on the relationship between body mass index （BMI） and health-related quality of life （HRQOL）. Methods A total of 1 114 participants were recruited from the Physical Examination Center of two hospitals. SF-36 was used to measure HRQOL, and the classification of sports level was done according to the subjective evaluation of participants. Results The total score of HRQOL,physical component summary and mental component summary were 76.26± 16.10,75.97 ± 16.67 and 76.55± 18.33 respectively.The results of correlation analysis were as following ：the positive correlation between BMI and general health（ r= 0.109）, vitality （ r= 0.116）, social functioning（ r= 0.092）, role emotional（ r= 0.122）, mental health（ r= 0. 145）were significant （P〈0.01）.The negative correlation between BMI and PF（ r=-0.07, P= 0.019）was significant.The mediation effects of exercise in was relationship between BMI and general health,vitality, mental health were significant, and the mediating effect were 5.84%, 9.14% and 6.58%. Conclusion This study demonstrates that mediation effects of the exercise are significant in some dimensions of HRQOL,but the direct influence of BMI on the HRQOL plays a leading role.And BMI is a protective factor under certain conditions.