Ruler Drop Method in Virtual Reality as an Accurate and Reliable Tool for Evaluation of Reaction Time of Mixed Martial Artists

Reaction time (RT) is one of the key factors in combat sports. Its high level is a predictor of sporting success. Therefore, RT tests are an important diagnostic tool in combat sports. The implementation of some conventional psychomotor tests in virtual settings can facilitate research and improve the objectivity and standardization of the measurement procedure. The main aim of the present study was to evaluate the reliability and validity of RT measurements, using the ruler drop method (RDM) implemented within immersive virtual reality (VR). Twenty-eight professional mixed martial arts (MMA) fighters were examined. The validity of the new VR measurement method was estimated by comparing the results obtained using the computer test and the conventional catch-the-ruler test. The reliability of the measurements was evaluated using an intraclass correlation procedure. Analysis of variance was used to examine the differences in RT in MMA fighters obtained from different tests. Significant correlations were found between the results of measurements in VR and the results of other tests, with the highest values observed between the tests performed in a virtual environment and computer-based tests. The values of the ICC intraclass correlation coefficients for all the reaction time tests conducted in the group of MMA fighters were at an adequate or high level. The analysis of variance showed that the reaction time of MMA fighters differed significantly between the tests. In VR and computer-based tests, reaction times were significantly longer than during conventional RDM measurements. RT did not depend on the hand used during the test. In conclusion, the VR environment allows for designing and conducting valid reaction time tests reliably and objectively, using standard testing procedures, while reducing the effect of human factors on the measurement results.