The Effects of Rotational Prisms on Badminton Players' Ocular Vergence Training and Enhancement of Shot Accuracy

This randomized controlled trial explores the application of vergence eye movement training in enhancing visuomotor performance in competitive badminton athletes. The intervention utilizes a device known as the Automatic Dual Rotational Risley Prisms (ADRRPs), which delivers alternating base-out and base-in prism stimulation in an automated manner to engage binocular vergence mechanisms. The study targets young adult badminton players with at least two years of consistent training. Participants are randomly allocated to either an experimental group, which receives active prism training using the ADRRPs, or a control group using an identical headset without prism rotation. Both groups undergo training sessions twice a week for four weeks, with each session lasting 15 minutes. Visual stimuli are standardized across groups and delivered at a fixed near working distance of 40 cm. The prism rotation parameters are set to simulate dynamic vergence demands based on pre-measured individual capabilities. This approach aims to create a structured vergence load while minimizing visual discomfort. The control condition serves to control for placebo and attentional effects. Outcome measures are selected to assess both oculomotor and performance domains. These include vergence facility, accommodative facility, near point of convergence, and positive fusional vergence-all measured using standardized optometric tools. Reaction time is assessed via a BlazePod light stimulus test, and hitting accuracy is evaluated through a shuttlecock launcher delivering randomized trajectories to simulate game-like performance. The trial design incorporates single-blinding and concealed allocation procedures. Data analysis will follow a pre-specified statistical analysis plan, and participants will be closely monitored for any adverse symptoms during the course of the intervention. Ethics approval has been obtained from the relevant institutional review board.