Abstract: In this paper, through the methods of testing and statistics, exercise load of 120 PE lessons of five middle school students has been tested and evaluated under the background of "sunshine sports" in order to reveal the current situation and problems of physical education exercise load for students. The results show that: (1) the exercise intensity of the tested 120 P.E. classes is moderate. For different grades, there are significant differences in heart rate indexes , with the descending order of heart rate index value of the whole class being senior one, junior two, senior three, senior two, junior one and junior three.(2) From the point of view different genders , the boys' exercise intensity in physical education lessons is moderate, but the structural changes in heart rate is unreasonable. (3) From different teaching contents, the descending order of heart rate index ranks as ball games, mixed class of quality ball games, athletics and ball games classes, athletics, aerobics and martial arts. The first three can be classified as moderate exercise load grades while the latter three are small load level range if divided according to exercise load levels. Therefore it is obvious that the teaching contents are the main factors that influence the physical load of P.E. lessons.

Key words: sunshine sports, middle school students, P.E. class, exercise load test