Perceiving the distances with a hand-held object and a lunge (in fencing)

The ability of perceiving the distances is essential in fencing. Perception of the distances with a hand-held object (a wooden stick or a fencing blade) in a lunge stance was examined under different conditions on fencers, tennis players and graduate students who had no extended experience in fencing or racket sports. Three different arm positions while holding a fencing blade and 2 different postures without holding a blade when approaching or moving away from participants were manipulated as the target to the perceived distance. Participants had to perceive the distances under each condition in a standing, hands-free position, and then their actual movement length was measured for comparison. All groups could distinguish the length difference between the 2 hand-held objects but both were overestimated. The smallest ratio of absolute errors were found in the fencers. Different target conditions did not affect participants’ judgments of the relative accuracy of the perceived length. All participants perceived longer distances when the target was approaching than moving away. Furthermore, body segments and lunge length are not significantly correlated, but fencers had longest lunge length. These results were interpreted as further evidence of systematically visual perception from Gibson’s ecological perspectives of information invariants and affordance.