To better assist speed skaters in scientific training, a human skeleton model was constructed from the perspectives of human mechanics and biomechanics. Based on the correspondence between the human skeletal model and the multi-body rigid body theory, the variation laws of angle and angular acceleration between human skeletal joints were deduced, and a dynamic model was constructed. An experimental study was conducted on the angle and angular acceleration changes of the lower limb joints of athletes during the speed skating process, with a period of 1 second. The experimental results showed that the left hip joint angle reached its maximum peak first, the left knee joint and left ankle joint lagged relatively, and the angle changes of the right knee joint were more severe; the angular acceleration of the left and right knee joints varies dramatically, causing significant impact on the athlete's knee joints. The research results of this article have important value for the scientific training of speed skaters. [ABSTRACT FROM AUTHOR]