School of Public Health, Physiotherapy and Sport Science, University College Dublin, Ireland.
Insight Centre for Data Analytics, University College Dublin, Ireland.
J Athl Train. 2020 May;55(5):494-500. doi: 10.4085/1062-6050-243-19. Epub 2020 Mar 27.
Many runners report "hitting The Wall" (HTW) during a marathon (42.2 km). However, the performance manifestation of this subjectively experienced phenomenon remains unclear.
To identify a pace-based classification for HTW by integrating subjective reports of fatigue and runners' pacing profiles during a marathon.
Cross-sectional study.
Public race event (2018 Dublin Marathon).
Eighty-three runners (28 [34%] women, 55 [66%] men, age = 41.5 ± 9.1 years, height = 1.73 ± 0.09 m, mass = 70.2 ± 10.1 kg).
MAIN OUTCOME MEASURE(S): The pacing profiles for respondents to our postrace questionnaire that concerned the phenomenon of HTW were evaluated. Receiver operating characteristic analyses were performed on discretized outcomes of the time series of marathoners' paces during the race.
Using the receiver operating characteristic analyses, we observed that runners could be classified as having experienced HTW if they ran any 1-km segment 11% slower than the average of the remaining segments of the race (accuracy = 84.6%, sensitivity = 1, specificity = 0.6) or if the standard deviation of the normalized 1-km split times exceeded 0.0532 (accuracy = 83%, sensitivity = 0.818, specificity = 0.8). Similarly, runners could be classified as having experienced HTW if they ran any 5-km segment 7.3% slower than the average of the remaining 5-km segments of the race (accuracy = 84.6%, sensitivity = 1, specificity = 0.644) or if the standard deviation of the normalized 5-km split times exceeded 0.0346 (accuracy = 82%, sensitivity = 0.909, specificity = 0.622).
These pace-based criteria could be valuable to researchers evaluating HTW prevalence in cohorts for whom they lack subjective questionnaire data.
许多跑步者在马拉松比赛中报告经历了“撞墙”(HTW)。然而,这种主观体验现象的表现仍然不清楚。
通过整合马拉松比赛中主观疲劳报告和跑步者配速模式,确定基于配速的 HTW 分类。
横断面研究。
公共赛事(2018 年都柏林马拉松)。
83 名跑步者(28 名[34%]女性,55 名[66%]男性,年龄=41.5±9.1 岁,身高=1.73±0.09m,体重=70.2±10.1kg)。
对我们赛后问卷调查中涉及 HTW 现象的回答者的配速模式进行评估。对比赛中跑步者的配速时间序列进行离散化处理后,进行受试者工作特征分析。
使用受试者工作特征分析,我们观察到,如果跑步者在任何 1 公里赛段的配速比比赛其余赛段的平均配速慢 11%(准确性=84.6%,敏感性=1,特异性=0.6),或者归一化 1 公里分段时间的标准差超过 0.0532(准确性=83%,敏感性=0.818,特异性=0.8),那么他们可以被归类为经历了 HTW。同样,如果跑步者在任何 5 公里赛段的配速比比赛其余 5 公里赛段的平均配速慢 7.3%(准确性=84.6%,敏感性=1,特异性=0.644),或者归一化 5 公里分段时间的标准差超过 0.0346(准确性=82%,敏感性=0.909,特异性=0.622),那么他们也可以被归类为经历了 HTW。
这些基于配速的标准对于研究人员评估缺乏主观问卷调查数据的队列中的 HTW 患病率可能具有重要价值。