I’m a little slow to catch up, because I’ve been involved in a number of things recently, but I’ve been reading up on Floyd Landis’ failed drug test. If you haven’t heard, the winner of this year’s Tour de France failed a test for testosterone levels after his stage win that put him back within reach of the yellow jersey.
I understand some of the science behind the test, in that an athlete’s ratio of testosterone to epitestosterone is measured and calculated. Normally epitestosterone production levels shadow testosterone levels, so the ratio is around 1:1. Exogenous testosterone added by injection or patch does not affect the levels of epitestosterone, so the ratio shifts in favour of testosterone. The UCI’s limits for bike racing are at 4:1. Landis’ ratio was at 11:1.
There are a number of things that really don’t add up for me here.
– Firstly, other than methods of quantifying it for drug testing, I don’t think epitestosterone is that well understood. Its functions, sites of synthesis or biosynthetic pathways have not been conclusively determined (as far as I am aware) and natural variations in quantity do occur (J Steroid Biochem Mol Biol. 2003 Oct;87(1):27-34). Those facts would make it a little worrying to me to use within a doping test.
– It is well known that doping tests compare testosterone levels with epitestosterone levels, so why do athletes get caught if testosterone doping is masked by epitestosterone injections? Are professional athletes stupid, or is it just a small mistake at the wrong time?
– Testosterone would not give an overnight improvement in ability. As an anabolic steroid, it is difficult to see how testosterone would account for the difference between Landis’ bad day on stage 16 and his great day on stage 17 (although they way the journalists write they certainly suggest that it would). For testosterone to have any useful affects it would need to be taken for a long period of time, so what do all of Landis’ other testosterone tests show? He has been racing successfully for a number of years, and will have been regularly tested.
– Landis is recorded as having drunk whiskey after his stage 16 disaster. It has been documented that ethanol ingestion affects the testosterone:epitestosterone ratio (J Chromatogr B Biomed Appl. 1996 Dec 6;687(1):109-16; Clin Chem. 1988 Jul;34(7):1462-4.) Evidence for the defense or a safety-line?
I’ll assume him innocent until proven guilty, but whichever way it falls international cycling has disappointed me again.
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One response to “Landis’ Testosterone”
Yes, I was also disappointed. In our local newscast they mentioned that the testosterone would not have taken effect that very next morning. However, they quickly dismissed the fact; favoring, instead, their allegations.