Shot is one of the throwing items in Track and field, and this event has a more significant role on physical enhancement, development of trunk and upper and lower limbs strength. Expectations of coaches and athletes are throwing the shot farther under the premise of not detrimental to health. The throwing distance of shot is related to the releasing speed and releasing position. The expression of speed includes the velocity size and velocity direction, the expression of position includes the coordinates in the horizontal direction and the vertical direction. This paper uses the principle of sports biomechanics, analyzes the whole process of backward sliding shot put and the movement condition after releasing shot, researches the promotion program for shot releasing speed and performance through biomechanical parameters, and establishes the mathematical model to solve the optimal angle of shot throwing. It uses Mathematical software to conduct numerical modeling and simulation on the movement trajectory after releasing shot and to verify the reasonableness of the optimal angle, uses the studying results to validate the existing backward sliding shot put technique and puts forward rationalization proposals.