Influence of shoe torsional stiffness on foot and ankle biomechanics during tennis forehand strokes

Abstract

Tennis shoe characteristics need to minimize the risk of athletes suffering ankle injuries and improve players' feet performance. This study aims to evaluate the influence of shoe torsional stiffness on running velocity, stance duration, ground reaction forces and ankle biomechanics during two different tennis forehand runs and strokes. Ten right-handed advanced male tennis players performed two specific tennis forehand runs and strokes at maximal effort (a shuttle run with a defensive open stance forehand -SRDF and a lateral jab run with an offensive open stance forehand -JROF) with four different pairs of tennis shoes with different torsional stiffness. A force platform measured ground reaction forces (GRF). A motion capture system recorded the 3D trajectories of markers located on players' anatomical landmarks. The minimum, maximum angle value, and range of motion were computed using inverse kinematics for each rotation axis of the right ankle. Normalized maximal ankle torques were also computed Highlights• Shoe torsional stiffness has no effect on performance parameters (running velocity of the center of mass, ground reaction forces, and stance duration) during tennis forehand strokes.• Decreased shoe torsional stiffness increased the maximal forefoot inversion angle and the range of motion of forefoot inversion-eversion during tennis forehand strokes and movements.• Increased footwear torsional stiffness causes higher maximal ankle inversion angle which may increase the risk for ankle sprains in SRDF.

Influence of altered torsional stiffness through sole modification of air pressure shoes on lower extremity biomechanical behaviour during side-step cutting maneuvers

“…The rotary head in the test machine is responsible for the rotation of the fixtures in a clockwise and anticlockwise direction that causes the shoe forepart movement against the stationary back part, and the movements are known as inversion and eversion of the shoe that could mimic the foot-shoe inversion/eversion motion. To measure the torsional stiffness of the shoe, the machine rotated the forefoot section of the shoe relative to the fixed rearfoot section with an angle of 30° of inversion and eversion, respectively, with angular speed of 1°/s [ 38 , 39 , 45 ] and sampling rate of 200 Hz [ 40 ].…”