Haematocrit levels.

Jun 12, 2010
Quick question. I was under the impression the 50% rule had changed.
If it has can anyone explain how and provide a link as to how.

If it hasn't can anyone let me know. Cheers peeps.

the big ring

Jul 28, 2009
Accidentally found what I think is the answer:

JV1973 said:
Certain new fixed blood values were in use starting in 2004...ie off-score of 133+ and you're out. also, obviously, the homologous transfusion test was in place in 2004. Individual profiling, ie looking at individual variation and comparing that to standard deviation, was not in use in 2004. The focus of ACE in 2008 and the current blood passport model is deviation of the individual's values from his norms. not fixed, standardized cross-population values such as 50% hct or 133 off-score.

here's a little factoid too: hematocrit hasnt been seen as big factor in anti-doping for quite some time. its all about hemoglobin and retic relationships. the 50% hct rule hasnt been in place for a while, as any small sample transport delay or exposure to heat can really mess with hct% by swelling the cells or even popping them. However, Hemoglobin is stable for much longer.