Surfing bottom turns underpin the quality of subsequent maneuvers, and surfing performance overall. Despite this, no study has investigated coaching cues to determine their association with performance. This study investigated the frontside bottom turn, to identify critical features associated with quality performance, and second to determine whether any of these features could predict whether a surfer would subsequently perform either a cutback or a top turn maneuver. Videos of every frontside bottom turn from all finals heats of the 2017 World Surf League, Corona Open Jeffrey's Bay event were analyzed. A total of 199 frontside bottom turns were identified and categorized as either a bottom turn leading to a cutback maneuver (n = 106), or a bottom turn leading to a top turn maneuver (n = 93). A checklist of 47 potential critical features was developed after consultation with coaching and competition judging experts, thereby enabling a systematic analysis of each turn to determine the expected and actual frequency of occurrence for each potential feature. Consequently, an extensive list of critical features of the frontside bottom turn was identified and associated with a high level of performance, being executed successfully by professional athletes during high‐stakes competition. Several features, particularly during the exit phase of the bottom turn, also helped predict whether these athletes subsequently performed either a cutback or a top turn maneuver. The findings of this study provide surf coaches with cues that can be used as a guide to effectively coach two main frontside bottom turn variations.

中文翻译：

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定性分析，以确定职业冲浪中正面底部转弯的关键特征


冲浪底部转弯是后续动作质量和整体冲浪性能的基础。尽管如此，还没有研究调查教练线索以确定它们与绩效的关系。这项研究调查了正面底部转弯，以确定与质量表现相关的关键特征，然后确定这些特征中的任何一个是否可以预测冲浪者随后是执行切入还是顶部转弯动作。分析了 2017 年世界冲浪联盟 Corona Open Jeffrey's Bay 赛事所有决赛预赛中每个前侧底部转弯的视频。总共确定了 199 个正面底部转弯，并将其分类为导致切入机动的底部转弯 （n = 106） 或导致顶部转弯机动的底部转弯 （n = 93）。在咨询教练和比赛评判专家后，制定了一份包含 47 个潜在关键特征的清单，从而能够对每个回合进行系统分析，以确定每个潜在特征的预期和实际出现频率。因此，确定了前侧下转的广泛关键特征列表，并与高水平的表现相关联，职业运动员在高风险比赛中成功执行了这些特征。一些特征，特别是在下转的退出阶段，也有助于预测这些运动员随后是执行切入还是上转动作。这项研究的结果为冲浪教练提供了线索，这些线索可以用作有效指导两个主要前侧底部转弯变化的指南。