Frame # 13 : left hand / forearm force application is backward and powered by upper arm adduction 画面13 :左手/小臂向后用力,并由上臂内收提供动力。
2.
Frame # 6 : the vigor of the right arm pull is evidenced by the amount of upper arm adduction that has occurred since the previous frame 画面6 :从上帧画面开始的上臂内收继续加大,这也使得右臂的划水力增大。