Does body position before and during blood sampling influence the Athlete Biological Passport variables?

Abstract

The Athlete's Biological Passport (ABP) is a tool for the indirect detection of blood doping. Current guidelines from the World Anti-Doping Agency (WADA) require a delay of 2 hours after any physical exercise and to be seated for 10 minutes prior to any blood sampling to obtain a valid measurement.Since body position prior to and during phlebotomy may influence the outcome, this study compared blood biomarker variations with changes in body position during blood sample collection. Ten successive venous blood samples from 38 subjects of 3 groups (elite cyclists, apnea divers and controls) in three situations (seated, after a 50 m walk, and supine) were collected and analyzed via flow cytometry. While reticulocytes percentage was unchanged in all conditions, haemoglobin concentration and hematocrit were stable after at least 10 min in a seated position. Due to shifts in plasma volume, the measures were significantly higher after changing posture for a short walk, but readjusted to previous levels after only 5 min. Supine position caused generally lower values after 10-30 min. The results support the current guidelines and additionally provide evidence to adjust the waiting time for blood sampling after short changes in posture.

Factors confounding the athlete biological passport: a systematic narrative review

“…The period of influence these factors had ranged from a few minutes (e.g. body position during sampling [13]) to a few hours (e.g. intense exercise [14]), and can, therefore, alter blood variables.…”

“…One group of swimmers lived high and trained high (LHTH, n = 10) for three to four weeks at 2130 m or higher, while a control group (n = 10) completed a three-week training camp at sea level. Haematological parameters were determined weekly three times before and four times after the training camps (+7, +14, +21 and +28 d)measured in13 elite cyclists during and 10 d after 3 weeks of sea level or altitude training (2760 m). The altitude group participated in a 3-week natural altitude training camp at Passo dello Stelvio, Italy, living at 2760 m and training during the majority of ride time > 1800 m for 2-6 h d −1 .…”

Annual banned‐substance review: Analytical approaches in human sports drug testing 2019/2020

“…For instance, the influence of the tested athlete's body position before and during the blood sampling procedure was assessed, indicating that %RET was unaffected while values measured for the hemoglobin concentration [Hb] and the hematocrit (Hct) differed slightly yet significantly, depending on the tested person's prior activity and body position. Consequently, a seated position for 5–10 min is recommended to obtain ABP data exempt from activity‐ or supine‐induced plasma volume (PV) shifts 181 . Studies on the potential influence of the menstrual cycle on ABP parameters indicated merely negligible effects 182 ; hyperhydration was shown to have no impact on ABP readings 183 ; and likewise, exercise‐induced sweating dehydration with an average loss of up to 3.1% of body mass was reported to have no effect on [Hb] during ABP testing, 184 demonstrating the robustness of the hematological module.…”

“…Consequently, a seated position for 5-10 min is recommended to obtain ABP data exempt from activity-or supine-induced plasma volume (PV) shifts. 181 Studies on the potential influence of the menstrual cycle on ABP parameters indicated merely negligible effects 182 ;…”

The influence of training load on hematological Athlete Biological Passport variables in elite cyclists

“…First, blood sample quality is paramount as there is a potential influence of pre-analytical procedures (e.g. position during sampling, sample transport) on the analytical results (Ahlgrim et al, 2010;Robinson et al, 2011;Ashenden et al, 2014;Astolfi et al, 2020). There are strict WADA guidelines for blood collection, transportation and storage to prevent variations due to such confounders (WADA, 2019b;a;c).…”