Effect of temporal occlusion of the attack action on defensive decision making in volleyball

This study examined the effect of temporal occlusion of a volleyball spike on the defensive decision-making of athletes with different levels of experience. The participants were divided in three groups: adult (GAD; n = 16), sub-17 (GIM; n = 16) and novice adult (GNO; n = 16). Images of attacks performed by 4 athletes were edited in five different moments: (OT1) 399 ms (12 frames) before the hitter's contact with the ball, (OT2) 266 ms (eight frames) before contact; (OT3) 133 ms (four frames) before contact; (OT4) at the moment of hitter's contact with the ball and; (OT5) 133 ms (four frames) after the hitter's contact with the ball. After watching the edited videos, participants were asked to predict the landing site of the ball, followed by the confidence with which they issued their responses. The precision in the prediction of the ball's trajectory (correct/incorrect) and the confidence of the response (1-5 Likert scale) were measured. Regarding the correct response frequency, the GAD (X = 63.67 ± 10.38%) group showed a greater frequency of correct responses than GIM (X = 55.46 ± 10.17%) in OT2 (p = 0.001) and the frequency of correct responses of GAD (X = 79.29 ± 10.38%) was also greater than GNO (X = 71.87 ± 10.43%) in OT3 (p = 0.012). The conditions were different from each other, with the frequency of correct responses increasing from OT1 (X = 36.06 ± 12.44%) to OT5 (X = 98.17 ± 4.81%). Regarding confidence, GAD and GIM were more confident than GNO in OT1, OT2 and OT3. Again, the conditions were different from each other, with the groups showing more confidence in OT5. We conclude that, regardless of experience, all groups were able to predict the landing site of the ball. However, groups with more experience were superior in their anticipatory ability.

本研究探讨了排球扣球动作的时间遮挡（temporal occlusion）对不同经验水平运动员防守决策的影响。研究对象被分为三组：成年组（GAD; n = 16）、17岁以下组（GIM; n = 16）以及新手成年组（GNO; n = 16）。研究人员对4名运动员的进攻动作影像进行编辑，选取5个不同时间节点制作刺激材料：OT1为击球手触球前399 ms（12帧），OT2为触球前266 ms（8帧），OT3为触球前133 ms（4帧），OT4为击球手触球瞬间，OT5为击球手触球后133 ms（4帧）。被试观看编辑后的视频后，需先预测排球的落地点，随后报告其作答的自信程度。本研究测量了两项指标：排球轨迹预测的准确性（正确/错误）以及作答自信程度（采用1~5李克特量表（Likert scale））。在正确作答频率方面，OT2时段成年组（平均正确率为63.67 ± 10.38%）的表现显著优于17岁以下组（55.46 ± 10.17%，p = 0.001）；OT3时段成年组（79.29 ± 10.38%）的正确作答率同样显著高于新手成年组（71.87 ± 10.43%，p = 0.012）。不同时间遮挡条件间的正确作答率存在显著差异，整体呈现从OT1（36.06 ± 12.44%）到OT5（98.17 ± 4.81%）逐步升高的趋势。在作答自信程度方面，OT1、OT2及OT3时段，成年组与17岁以下组的自信评分均显著高于新手成年组。同样，不同时间遮挡条件间存在显著差异，所有组别在OT5时段的自信程度最高。本研究得出结论：无论经验水平如何，所有组别均能够预测排球落地点。但经验更丰富的组别在预判能力上表现更优。