A coupled biomechanical-Smoothed Particle Hydrodynamics model for predicting the loading on the body during elite platform diving

• A biomechanical model of a platform diver is coupled to an SPH model of water.
• Body segment forces and joint torques after water entry are calculated.
• Loading on the body is dangerously large especially on the hands and torso.
• Mistiming of a dive changes the timing and magnitudes of body loading.
• Injury risk of different dives, technique and athlete body shape can be investigated.

Platform diving injuries are common, especially in the arms, neck and back, and appear to arise from cumulative damage from multiple overload events as well as singular cases of acute loading. Experimental measures of forces on the body are impractical so instead computational simulation is used to estimate this loading. A coupled Biomechanical-Smoothed Particle Hydrodynamics (B-SPH) model for diver and water is developed and applied to a reverse pike dive performed by an elite athlete. The body surface is represented by a mesh that deforms in response to measured skeleton kinematics acquired from multi-camera video. Calculations of the fluid forces on the body and the transmission of torque through the upper body joints are made. Loading on the body segments and joints is found to be closely related to the dynamic behaviour of the body and water. The sensitivity of the results of the model to variations in water entry pitch angle (EPA) is explored. Simulation results suggest that altering the timing of contact between the water and different body segments changes the loading and potentially the injury risk of the dive. The simulation framework presented shows promise as a tool for coaches and sports scientists to evaluate the performance, strength requirements and safety of diving technique.