Integration of planned behavior theory and environmental variables to explain physical activity participation. The Journal of Kinesiology, 2017, 19(4): 47-56. [PURPOSE] The purpose of this study was to identify the motivators of physical activities by applying the planned behavior theory to adults as the subjects. [METHODS] Four hundreds fifty adults in sports and cultural facilities in S district in Seoul participated in the research. Also, attitude, subjective norm, behavioral control perception, behavioral intention, physical environment and physical activity questionnaire were used as measurement tools. [RESULTS] Descriptive statistics, correlation analysis and path analysis were utilized. The results are as follows. Attitude, subjective norm, behavioral control perception and physical environment were shown to have a significant influence on behavioral intention. Whereas intention and behavioral control perception had a direct effect on physical activities, physical environment did not affect physical activities. However, through the extension model, it was confirmed that physical environment influences behavioral intention. [CONCLUSIONS] These results suggest that integrated research related to socio-environmental variables that may affect physical activity is needed. This study can contribute to the development of the psychological theory through multidimensional interpretation.