Visual search strategies of Judo coaches

Judo contests present complex situations to judo coaches observing them. The visual search strategies employed by coaches when observing contests will be used to inform coaching decisions. To date, there have been no investigations of judo coaches’ search strategies; therefore, this series of exploratory experiments investigated the search strategies of elite, sub-elite, and non-judo coaches when observing elite-level judo contests. Participants observed video footage of contests, with eye movements recorded using a mobile eye tracker. Participants were instructed to provide verbal instructions at set times to improve a specified judoka's (judo athlete) performance. Eye movements from contest preparation phases was analysed using summary fixation data, and entropy and transition data derived from Markov chain modelling. A preliminary investigation of approaches used for analysing summary fixation data was undertaken (chapter 5: Experiment 1). This chapter, which served to inform subsequent experimental chapters, identified minimal differences between dwelland fixation-based approaches during contest preparation phases. Chapter 6: Experiment 2 identified that elite coaches fixated more frequently and for longer on the specified judoka’s upper body compared to the opponent’s upper body and other areas in the display. However, sub-elite and non-judo coaches demonstrated no difference in fixation frequency or duration between the judokas' upper bodies. Chapter 7: Experiment 3 and chapter 8: Experiment 4 respectively examined the influence of prior exposure to contest information, and previously viewing a contest. Sub-elite and elite coaches did not change their search strategies despite prior exposure to contest information, or when viewing previously observed contests. However, chapter 7: Experiment 3 identified that non-judo coaches altered their search strategy, becoming similar to elite coaches following prior exposure to contest information. It is possible that use of on-screen instructions contributed to the change in search strategy. Chapter 9: Experiment 5 investigated transitions between areas of interest (AOIs) and entropy. No between-group differences in transitions or entropy were observed. Elite coaches’ strategy of fixating more frequently and for longer on the specified judoka’s upper body is likely the result of employing this AOI as a visual pivot, using central vision to obtain information about the judoka, and peripheral vision to obtain information about the opponent. Sub-elite coaches appeared to rely on central vision to obtain information about each judoka. Developing a similar strategy to elite coaches may benefit sub-elite coaches.