In combat sports, gaze behaviour, visual search and (visual) anticipation have been studied within a range of different disciplines (judo [1], karate [2], fencing [3]). Expert taekwondo athletes can perform a roundhouse kick under 200 ms [4]. However, the time between a non-anticipated stimuli and the onset of a response of the taekwondo athlete has been found to be between already 145-223 ms [5]. These numbers illustrate the importance of the ability to predict the actions of the opponent before they have started to move.

Pick-up of visual cues (from the kinematics of your opponent) is considered one category that contributes to anticipation in sports [6] and should include, in some manner, an awareness of what the opponent is able to do (and not do) given their relative position. One possibility is that action boundaries, regions that separate possible and impossible actions [7], are a source of information shaping anticipation to successfully block, slip or counter, and maintain the ability to achieve a given action.

It is well known that, particular distances to a target result in the use of different techniques [8] (e.g. the distance where boxers showcase straight punches is different than the distance where hocks emerge).  Furthermore, certain interpersonal distances afford certain actions for both the athlete and the opponent [9]. During sparring, expert martial arts athletes appear more aware of the zones where attack and defence moves are afforded and adjust their behaviour accordingly (e.g., expert kendo athletes adjust their stepping behaviour more rapidly than intermediate kendo athletes to the striking affordances, continuously moving in and out the attack and defence zones) [9]. Therefore, the purpose of this research is to examine how gaze behaviour might be shaped by changes in action boundaries during sparring.

Research question

Are expert kickboxers better attuned to action possibilities than intermediate kickboxers? Is gaze behaviour scaled to these action possibilities?

Method and design

Two groups will be recruited based on skill criteria. A beginner group will be formed of kickboxers with 3-12 months experience with sparring in training, and a second expert group will be formed of kickboxers currently competing in amateur kickboxing competitions. During the sparring sessions, visual scan-paths and interpersonal distance will be recorded using eye trackers and video cameras. In a pre-test the action zones for a selection of punches and kicks will be established using a boxing bag that registers impact force and location. Experts are expected to be more sensitive to these action zones during sparring than intermediate kickboxers. Exhibiting the selected techniques only within the corresponding action zones. Furthermore, they are expected to adjust their visual scan strategy (gaze behaviour) to the actions possible within that specific action zone.



Photos, Glory 52: 31 March 2018. Robin van Roosmalen vs Kevin Vannostrand



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