In this paper, the subjective degrees of physical activity based on heart rate(HR) were examined. In order to evaluate the difference of subjective degrees of physical activity with AIHA(American Industrial Hygiene Association), two groups of subjects were recruited from assembly workers and football players as university students and they were instructed to run on a treadmill at different speeds. Restricted within the limit of this experiment, we gained such results that the subjective degrees of physical activity represented as adjective and heart rate in this study is different from that of AIHA bases.