Mizawa Takayasu, Okumura Motoki, Kijima Akifumi
Faculty of Sport Sciences, Yamanashi Gakuin University, Kofu, Japan.
Faculty of Education, Tokyo Gakugei University, Koganei, Japan.
Front Sports Act Living. 2022 Apr 12;4:867743. doi: 10.3389/fspor.2022.867743. eCollection 2022.
In real hockey or soccer games, scoring opportunities usually occur quite rarely, and thus, for most of the duration of a game, the ball is drifting between the two goals. This pass-chaining situation can be regarded as the stable state of the offense-defense interaction. In the current study, temporal and spatial structure of this dynamical state was unveiled quantification of the "defensive pressure distribution" on the pass trajectory, which was modeled as a non-linear function of the distance between the defender(s) and a given position on the pitch. Two groups, i.e., a top-level group and a less-skilled group, of Japanese collegiate hockey players were asked to play in 3-on-3 small-sided games between players of the same skill levels. When both the top-level and less-skilled players succeeded in passing the ball, there were no skill-level differences observed in the defensive pressure distribution on the pass trajectory. In these cases, the defenders put a certain level of pressure on the middle of the pass trajectory when the passer received a previously released pass, and later, when he released the ball to a teammate, the defenders approached the position at which the passer released the ball to intensively press on the passer. However, in the cases wherein they failed to thread the ball, clear differences were observed between the groups in terms of the defensive pressure distribution on the pass trajectory. In particular, for the less-skilled group, extremely intensive defensive pressure was put on the overall regions of the pass trajectory heavily concentrated on the timing at which the passer released the pass. This unique pressure distribution emerged for the less-skilled group because of their long ball-keeping duration (longer than 1 s and also longer than that for the top-level group), i.e., from the moment the passer received the ball, to the moment he released it to the next attacker. Thus, for top-level hockey players, a short time constant (less than 1 s) for the passing action will enable the passers to avoid extremely intensive defensive pressure, and enable the emergence of a dynamically stable attack-defense deadlock state through continuous chaining of the pass.
在实际的曲棍球或足球比赛中，得分机会通常很少出现，因此，在比赛的大部分时间里，球都在两个球门之间来回传递。这种传球链的情况可以被视为攻防互动的稳定状态。在当前的研究中，通过对传球轨迹上“防守压力分布”进行量化，揭示了这种动态状态的时间和空间结构，该分布被建模为防守球员与球场上给定位置之间距离的非线性函数。两组日本大学生曲棍球运动员，即高水平组和低水平组，被要求在同水平球员之间进行3对3的小型比赛。当高水平和低水平球员都成功传球时，传球轨迹上的防守压力分布没有观察到技能水平差异。在这些情况下，当传球者接到之前传出的球时，防守球员会在传球轨迹的中间施加一定程度的压力，然后，当他将球传给队友时，防守球员会接近传球者传球的位置，对传球者进行密集施压。然而，在他们传球失误的情况下，两组在传球轨迹上的防守压力分布方面存在明显差异。特别是对于低水平组，在传球轨迹的整个区域都施加了极其密集的防守压力，且压力高度集中在传球者传球的时刻。这种独特的压力分布出现在低水平组中是因为他们持球时间长（超过1秒，也比高水平组长），即从传球者接到球的那一刻，到他将球传给下一个进攻者的那一刻。因此，对于高水平曲棍球运动员来说，短的传球动作时间常数（小于1秒）将使传球者能够避免极其密集的防守压力，并通过连续的传球链形成动态稳定的攻防僵局状态。
