Could this happen naturally?

[gt6267a]

Of the 189 medical checkups performed at the start of the Tour, the average hematocrit was 44.8% and the average haemoglobin was 14.9g/dl. As the Tour progressed, there were 107 additional blood controls carried out before July 13, which showed averages of 43.3% for hematocrit and 14.6g/dl for haemoglobin. During the last week of the Tour, 80 blood controls were performed, and the average hematocrit and haemoglobin were 42.3% and 14.1g/dl respectively.

throughout the tour the hematocrit level drops from 44.8% to 43.3% to 42.3%. i'm not familiar with these types of numbers and whether it is possible for this to happen naturally, but it looks suspicious. i.e. riders were taking epo before the tour and then the effects fell off throughout the tour. not sure if that is possible...

not sure about the haemoglobin stats, but there appears to be a similar trend.

thoughts?


http://www.cyclingnews.com/news.php?id=news/2004/jul04/jul30news3

[coylifut]

In February, my hetatocrit was 43%. It's now 39%. Then, I was very well rested, but not nearly as fit. Now, I'm very fit, but far from well rested. So for me, it occured naturally. However, I'm not convinced that anything occurs naturally in the pro peleton.

[Dekonick]

Hemacrit does change with alot of factors, including altitude, illness, workload on body, etc. It shouldnt change FAST unless you are bleeding or have something else causing you to lose blood cells...but your entire red blood cell population is completely replaced a couple of times a year naturally... :banana:

[malcolm]

Hydration also will change hgb/hct, although as you become dehydrated you become hemoconcentrated so from looking at those numbers they seem to be maintaining good hydration. I suspect as mentioned previously the decrease is from the stress of the event vs waning of epo. The life cycle of an epo red cell would be the same 120 days as a naturally produced one.

[oracle]

yes it is natural for heamatocrit to drop following a three week stage race if one is not blood-doped or on drugs.