In order to quantitatively evaluate the effect of sports training, it is necessary to track the dynamic characteristics of sports by using sports training aided decision support system. When the existing sports training assistant decision support system extracts the features of decision association rules, some redundant features will appear when establishing the global association rules, which increases the amount and difficulty of data calculation and affects the effect of assistant decision support. On this basis, the data fusion of assistant decision support information is carried out, and the optimal assistant decision support scheme is obtained according to the fusion results. The experimental results show that the design system is superior to the existing auxiliary decision-making system in motion recognition rate, motion result accuracy rate, and decision-making accuracy rate, which can provide users with auxiliary decision-making support for sports training and has good practical application effect.