Some time ago the Cycling Independent Reform Commission (CIRC) issued a report on performance enhancing drugs in bicycle racing, which makes clear that there is vigorous competition between drug taking and drug testing...
"The days of 15 percent gains in performance through massive EPO doping seem to be a thing of the past, according to CIRC. Instead, riders are skirting the edges of the anti-doping system, taking advantage of Therapeutic Use Exemptions, using overnight gaps in testing and a deep understanding of the Biological Passport to micro-dose without getting caught. Some are taking drugs that aren’t yet banned, like Tramadol, and using pill regimens that dull pain or improve recovery.
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"The Athlete’s Biological Passport (ABP), enacted in 2008, is named as a primary catalyst of the change, and a “paradigm shift.”
"CIRC wrote: “Prior to the ABP, only three riders were convicted of blood doping. In the first three years of the ABP, 26 riders were found positive for the presence of EPO stimulating agents in their specimens. In 20 out of the 26 positive cases, it was the abnormal blood profile which raised suspicions leading to a targeted anti-doping urinary or blood test.”
"An unheralded but important landmark in the decrease in doping, according to CIRC, was the introduction in 2008 of anti-doping chaperones at all UCI races. The report cites this change as a catalyst to a cleaner peloton, as riders could no longer quickly prepare for a test with masking agents or similar dodges.
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"The CIRC concluded that it is still possible to micro-dose using EPO without getting caught by the Biological Passport, largely thanks to the lack of nighttime testing.
"The lack of testing between 11 p.m. and 6 a.m. is a problem, according to the report. Testers are currently barred from testing riders between these hours, unless a rider is under suspicion. This allows for micro-dosing, as “riders are confident that they can take a micro-dose of EPO in the evening because it will not show up by the time the doping control officers could arrive to test at 6 a.m.”
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"CIRC wrote: “Corticoids are widely used today both to reduce pain and therefore improve endurance capability and to achieve weight loss to improve power/weight ratio.”
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CIRC Report: Executive summary
"The general view is that at the elite level the situation has improved, but that doping is still taking place. It was commented that doping is either less prevalent today or the nature of doping practices has changed such that the performance gains are smaller. The CIRC considers that a culture of doping in cycling continues to exist, albeit attitudes have started to change. The biggest concern today is that following the introduction of the athlete biological passport, dopers have moved on to micro-dosing in a controlled manner that keeps their blood parameters constant and enables them to avoid detection. In contrast to the findings in previous investigations, which identified systematic doping organised by teams, at the elite level riders who dope now organise their own doping programmes with the help of third parties who are primarily outside the cycling team. At the elite level, doping programmes are generally sophisticated and therefore doctors play a key role in devising programmes that provide performance enhancement whilst minimising the risk of getting caught."