Understanding and characterizing confounding factors to the Athlete Biological Passport (ABP) is crucial for the reliable interpretation of biological profiles in the antidoping field. The physiological effects on hematological parameters and plasma volume (PV) following competition in a long‐distance triathlon, as seen in the Ironman discipline, have yet to be fully described and are the focus of this study. Complete blood count blood tests were conducted on 19 Ironman triathletes before and after an Ironman triathlon to characterize changes in hematological parameters and the effect on ABP interpretation, as it was hypothesized that changes in the plasma volume may result in the presentation of atypical ABP profiles. Baseline blood samples were collected from the athletes prior to the event, and one sample was collected per day for up to 1 week following the race. Differences were observed between the male and female athletes across multiple parameters. Most importantly to the ABP, decreases in hemoglobin concentration (HGB) and hematocrit (HCT) were identified post‐race, with the largest decreases identified on day +2. The average HGB returned to pre‐race baseline levels on day +5. Beginning 5–6 days after the race, increases in the reticulocyte percentage (Ret%) were identified. Atypical Passport Findings were identified in 32% (6/19) of the ABPs, flagged mainly due to atypical hemoglobin concentration and one instance in which the OFF‐score exceeded the adaptive model limits. These results offer a characterized timeline of hematological changes and expected shifting of plasma volume following an Ironman triathlon providing important data for the reliable interpretation of ABP profiles in this field.

中文翻译：

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铁人三项铁人三项赛后的血液学变化：一种反兴奋剂的观点。

理解和表征运动员生物护照（ABP）的混杂因素对于在反兴奋剂领域可靠地解释生物学特征至关重要。在Ironman学科中，长距离铁人三项比赛后对血液学参数和血浆容量（PV）的生理影响尚未得到充分描述，这是本研究的重点。在Ironman铁人三项赛之前和之后，对19名Ironman铁人三项运动员进行了全血细胞计数血液测试，以表征血液学参数的变化以及对ABP解释的影响，因为有人认为血浆体积的变化可能会导致非典型ABP谱的出现。比赛前从运动员那里收集基线血样，比赛结束后的1周内，每天收集一次样本。男性和女性运动员在多个参数之间观察到差异。对于ABP而言，最重要的是在赛后发现血红蛋白浓度（HGB）和血细胞比容（HCT）下降，最大下降出现在第2天。在第5天，平均HGB返回赛前基线水平。比赛后5-6天开始，网织红细胞百分比（Ret％）有所增加。在32％（6/19）的ABP中发现了非典型护照的发现，主要由于非典型的血红蛋白浓度和一个OFF分数超过自适应模型限制的情况而被标记。