LifeMOD and Nike, Simulating the leg-foot during a drop landing
Client:
Nike
Business:
Manufacturer of apparel, shoes, and accessories
Challenge:
Cushioning the foot while simultaneously stabilizing the ankle can appear to be mutually exclusive requirements. If the shoe has too much cushion, is the foot more likely to roll over producing an ankle injury? If the shoe is stiffer and stabilizes the ankle, is too much shock transmitted to the body? These complicated variable couplings must be explored in detail to develop optimized sport shoes.
Solution:
An experiment was conducted where the human subject fell onto a force plate after releasing a hang bar. The force plate recorded the ground reaction forces, and motion capture equipment was used to capture the motion of the “jump landing”.
A LifeMOD™ model of a detailed foot and leg was generated complete with the lateral ligament complex in the ankle. The motion capture data was used in the model in an inverse-dynamics method to train the muscles in the model to produce similar kinematic behavior as observed in the experiment. The model was validated by comparing the ground reaction force created in the model to those recorded in the experiment.
Various conditions were simulated, including a condition where an obstacle was placed under the medial aspect of the forefoot to simulate an athlete landing on another player's foot during a jump landing. Strain in the lateral ligament complex was recorded to evaluate the injury potential.
A LifeMOD™ model of a detailed foot and leg was generated complete with the lateral ligament complex in the ankle. The motion capture data was used in the model in an inverse-dynamics method to train the muscles in the model to produce similar kinematic behavior as observed in the experiment. The model was validated by comparing the ground reaction force created in the model to those recorded in the experiment.
Various conditions were simulated, including a condition where an obstacle was placed under the medial aspect of the forefoot to simulate an athlete landing on another player's foot during a jump landing. Strain in the lateral ligament complex was recorded to evaluate the injury potential.
Value:
This validated model of a jump landing can now be used to evaluate various sports shoe mid-sole configurations to optimize shock attenuation and stabilize the ankle.
See publication.
See publication.