Simulation study of the importance of biarticular muscles on human vertical jump performance

The aim of this study was to quantify the importance of biarticular muscles on vertical squat jump. In order to do that, we used a neuromusculoskeletal model and a forward dynamics computer simulation. In separate trials biarticular muscles were removed from the neuromusculoskeletal model, firstly only one muscle was removed each trial, and then all three biarticular muscles were removed together in one more trial. Investigated were three main groups of biarticular muscles of lower extremities: m. rectus femoris, hamstrings and m. gastrocemius. The results demonstrated that monoarticular muscles are primary producers of the force used to accelerate the body’s centre of gravity vertically. While the function of biarticular muscles is twofold: Therefore, we conclude that the most important function of biarticular muscles in a vertical jump is to help to coordinate jump movement and increase the effectiveness of the usage of muscle force to accelerate vertically the body’s centre of gravity.