The Influence of Training Load on Hematological Athlete Biological Passport Variables in Elite Cyclists

Abstract

The hematological module of the Athlete Biological Passport (ABP) is used in elite sport for antidoping purposes. Its aim is to better target athletes for testing and to indirectly detect blood doping. The ABP allows to monitor hematological variations in athletes using selected primary blood biomarkers [hemoglobin concentration (Hb) and reticulocyte percentage (Ret%)] with an adaptive Bayesian model to set individual upper and lower limits. If values fall outside the individual limits, an athlete may be further targeted and ultimately sanctioned. Since (Hb) varies with plasma volume (PV) fluctuations, possibly caused by training load changes, we investigated the putative influence of acute and chronic training load changes on the ABP variables. Monthly blood samples were collected over one year in 10 male elite cyclists (25.6 ± 3.4 years, 181 ± 4 cm, 71.3 ± 4.9 kg, 6.7 ± 0.8 W.kg−1 5-min maximal power output) to calculate individual ABP profiles and monitor hematological variables. Total hemoglobin mass (Hbmass) and PV were additionally measured by carbon monoxide rebreathing. Acute and chronic training loads–respectively 5 and 42 days before sampling–were calculated considering duration and intensity (training stress score, TSSTM). (Hb) averaged 14.2 ± 0.0 (mean ± SD) g.dL−1 (range: 13.3–15.5 g·dl−1) over the study with significant changes over time (P = 0.004). Hbmass was 1030 ± 87 g (range: 842–1116 g) with no significant variations over time (P = 0.118), whereas PV was 4309 ± 350 mL (range: 3,688–4,751 mL) with a time-effect observed over the study time (P = 0.014). Higher acute–but not chronic—training loads were associated with significantly decreased (Hb) (P <0.001). Although individual hematological variations were observed, all ABP variables remained within the individually calculated limits. Our results support that acute training load variations significantly affect (Hb), likely due to short-term PV fluctuations, underlining the importance of considering training load when interpreting individual ABP variations for anti-doping purposes.

Gene Doping with Peroxisome-Proliferator-Activated Receptor Beta/Delta Agonists Alters Immunity but Exercise Training Mitigates the Detection of Effects in Blood Samples

“…An increase of about 75% of the maximum rate of fat oxidation (whole body measure), which is already high in elite endurance athletes, is observed after a 2 h recovery in a fasting condition from an endurance exercise session [ 22 , 23 , 24 ]. As both exercise and GW0742 alter fatty acid availability, we considered it important to choose the most appropriate experimental conditions in mice that allowed discriminating GW0742 effects from those induced by exercise, considering that the signature of an increase in FAO in T cells would be interpreted in an individual athletes’ biological passport [ 25 ] as a doping signature. Information is available on the internet regarding the oral doses of GW0742 used by athletes for the purpose of doping.…”

A single field test evaluation for the assessment of the Record Power Profile in cycling

“…kg -1 ) competing at an international level (UCI Elite International license) in track cycling, mountain-bike and road cycling were recruited. This study was conducted with the data collected in a study monitoring their training and hematological variables over 12 months (Astolfi et al, 2021) so that all subjects provided an informed written consent for the use of their data. The study was approved by the regional research ethics committee (CER-VD, Lausanne, Switzerland, #2018-01019) and conducted in respect of the Declaration of Helsinki.…”

Removal of the influence of plasma volume fluctuations for the athlete biological passport and stability of haematological variables in active women taking oral contraception

“…However, because the ABP relies on numerous concentration‐based biomarkers, such as [Hb] and OFFs, shifts in plasma volume (PV) may impair the interpretation of single ABP profiles with many sources of PV variation in athletes (e.g. exercise training, hydration, exposure to extreme environments [heat/cold or altitude] and competitions) 11–19 . In this context, a multi‐parametric model to remove the influence of PV shifts has been proposed 20,21 and was recently validated for the variance caused by altitude exposure in endurance athletes, 22 such as that experienced by elite cyclists during a stage race 23 .…”

“…exercise training, hydration, exposure to extreme environments [heat/cold or altitude] and competitions). 11 , 12 , 13 , 14 , 15 , 16 , 17 , 18 , 19 In this context, a multi‐parametric model to remove the influence of PV shifts has been proposed 20 , 21 and was recently validated for the variance caused by altitude exposure in endurance athletes, 22 such as that experienced by elite cyclists during a stage race. 23 The model appeared capable of reducing the influence of PV on concentration‐dependent markers of the ABP, with approximately 68% of PV variance explained, and it could also be applied in female athletes to test for actual PV shifts during the menstrual cycle.…”