Weich Christian, Barth Valentin, Killer Nikolai, Vleck Veronica, Erich Julian, Treiber Tobias
Sports Science Department, University of Konstanz, Konstanz, Germany.
Physics Department, University of Konstanz, Konstanz, Germany.
Front Sports Act Living. 2022 Dec 16;4:1065741. doi: 10.3389/fspor.2022.1065741. eCollection 2022.
Running in a triathlon, a so-called brick run, is uniquely influenced by accumulated load from its preceding disciplines. Crucially, however, and irrespective of race type, the demands of a triathlon always exceed the sum of its parts. Triathletes of all levels commonly report subjectively perceived incoordination within the initial stages of the cycle run transition (T2). Although minimizing it, and its influence on running kinematics, can positively impact running and overall triathlon performance, the mechanisms behind the T2 effect remain unclear. In the present study, we assessed the influence of the pre-load exercise mode focusing on the biomechanical perspective. To analyze inertial sensor-based raw data from both legs, the so-called Attractor Method was applied. The latter represents a sensitive approach, allowing to quantify subtle changes of cyclic motions to uncover the transient effect, a potentially detrimental transient phase at the beginning of a run. The purpose was to analyze the impact of a pre-load on the biomechanics of a brick run during a simulated Olympic Distance triathlon (without the swimming section). Therefore, we assessed the influence of pre-load exercise mode on running pattern (M) and precision (D), and on the length of the transient effect (t) within a 10 km field-based run in 22 well-trained triathletes. We found that D, but not M, differed significantly between an isolated run (I) and when it was preceded by a 40 km cycle (T) or an energetically matched run (R). The average distance ran until overcoming the transient phase (t) was 679 m for T, 450 m for R, and 29 4 m for I. The results demonstrated that especially the first kilometer of a triathlon run is prone to an uncoordinated running sensation, which is also commonly reported by athletes. That is, i) the T2 effect appeared more linked to variability in running style than to running style ii) run t distance was influenced by preceding exercise load mode, being greater for a T than for the R condition, and iii) the Attractor Method seemed to be a potentially promising method of sensitively monitoring T2 adaptation under ecologically valid conditions.
在铁人三项赛中进行的所谓“砖式跑步”，会受到其前序项目累积负荷的独特影响。然而，至关重要的是，无论比赛类型如何，铁人三项赛的要求总是超过其各个部分的总和。各级铁人三项运动员普遍表示，在自行车 - 跑步转换（T2）的初始阶段会主观感觉到不协调。尽管尽量减少这种不协调及其对跑步运动学的影响可以对跑步和铁人三项赛的整体表现产生积极影响，但T2效应背后的机制仍不清楚。在本研究中，我们从生物力学角度评估了预负荷运动模式的影响。为了分析来自双腿的基于惯性传感器的原始数据，应用了所谓的吸引子方法。后者是一种灵敏的方法，能够量化循环运动的细微变化以揭示瞬态效应，即在跑步开始时可能有害的瞬态阶段。目的是分析在模拟奥运距离铁人三项赛（不包括游泳部分）期间预负荷对“砖式跑步”生物力学的影响。因此，我们评估了预负荷运动模式对22名训练有素的铁人三项运动员在10公里实地跑步中的跑步模式（M）、精度（D）以及瞬态效应时长（t）的影响。我们发现，在单独跑步（I）以及在其之前进行40公里自行车骑行（T）或能量匹配的跑步（R）时，D存在显著差异，而M没有。直到克服瞬态阶段（t）的平均跑步距离，T组为679米，R组为450米，I组为294米。结果表明，特别是铁人三项赛跑步的第一公里容易出现不协调的跑步感觉，运动员也普遍有此报告。也就是说，i）T2效应似乎更多地与跑步风格的变异性有关，而不是与跑步风格本身有关；ii）跑步t距离受先前运动负荷模式的影响，T组比R组更大；iii）吸引子方法似乎是一种在生态有效条件下灵敏监测T2适应性的潜在有前景的方法。
