[Analysis on the relations between levels of change and the mental decisive factors on the physical exercise behavior among middle school students].

Objective: To study the situation of sports and its influencing factors among students in order to improve health related education and promotion programs.

Methods: A multistage random sampling method was used on 3 600 students from three cities to understand their physical exercise behavior. Both t and χ(2) test were used to measure the scale of psychology and to describe the time spent on exercise.

[The adolescent physical exercise behavior-psychological measurement scale on the Chinese version and its reliability and validity study].

Objective: To develop a suitable physical exercise behavior-psychological scale for the Chinese adolescents and to evaluate its validity and reliability.

Methods: A total of 3600 junior students were recruited and tested through multistage sampling method. Reliability was assessed, using Cronbach's α and split-half reliability; while exploratory factor analysis and confirmatory factor analysis were used to test its validity, with entries-dimension correlation coefficient (IIC), correlation coefficient between the scores and the dimension, the dimension of correlation coefficient test content validity.