Hyper responder. Maybe he has a natural low haematocrit? I heard Armstrong was in the 30s naturally
A naturally low Hct wouldn't matter under the current ABP system. For the hematological module, the system is based on the rider's baseline Hct level where individualized reference ranges are established. Abnormal fluctuations outside the reference ranges is what flags an athlete's ABP.
Bjarne Riis rode for
Gewiss-Ballan in 1994-95. The team had a systematic EPO doping program under the auspices of team doctor
Michele Ferrari. The blood values & Hct variations of the team's top riders were later published. Riis reportedly had a baseline Hct of
41.1 in Jan/1995 & was doped up to
56.3 for the 95 Tour (15.2 increase or 37% over baseline). Riis wore Yellow for a few stages & went on to finish on the podium behind Zulle (confirmed doper) & Indurain (suspected doper).
If the ABP was applied to his numbers, it would have been flagged for an atypical profile due to an exceptionally high Hct concentration = massive erythrocytosis. An OFF-score in the
140s would result from the 37% increase over baseline. OFF-scores over 140 are deemed 99.99 specificity with
less than 1 in 10,000 chance of being undoped. Normal OFF-scores typically range between 85-95. This would have been a cut & dry hematological anomalies case & Riis would have been banned.
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