One of anti-doping's biggest challenges is proving how a substance entered an athlete's body. Subsequently, the responsibility has been placed upon the athlete to prove how a substance has came into their body under WADA's Code of 'strict liability'.
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With anti-doping labs analytical sensitivity improving, athletes testing positive due to contamination of supplements for trace amounts of PED's offers a real concern to both athletes and the anti-doping authorities.
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Britain's CJ Ujah part of the Olympic 4x100m relay team who won the silver medal at the Tokyo Olympics has returned an AAF for the Selective Androgen Receptor Modulator's (SARM'S) Ostarine & S-23. He is likely to claim a contaminated supplement is the reason behind his AAF
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SARM'S currently under medical clinical trials are not approved for human consumption. SARM's offer a potential performance advantage designed to have an anabolic (muscle building) effect whilst minimising the negative androganising effects of anabolic steroids/testosterone.
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SARM'S are a drug which frequently turn up in supplements often not cited on the labels. A recent article by @JournoAndy stated over 200 supplements contain SARM'S, 98 containing Ostarine and 9 containing S-23.
Ostarine appears the most popular SARM of choice responsible for 148 AAF's between 2015 and 2018.
Clearly a popular PED of choice, but also prevent in supplements.
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DOI: 10.1002/dta.2933
Smart athlete's may try to Micro-dose SARM'S to gain the performance benefits whilst minimising the chances of testing positive. A recent 2020 study shows:
'Elimination profiles of microdosed ostarine mimicking contaminated products ingestion'
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Walpurgis et al (2020) study investigated the metabolism and elimination of ostarine metabolites from both a single dose along with multiple doeses of 1, 10 and 50ug of ostarine.
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A single dose of Ostarine 50ug was detectable for a maximum of 11 days, 1ug was detected a maximum of 9 days after administration.
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5 x 50ug of Ostarine could be detected for a maximum of 15 days.
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Low levels of a SARM'S metabolites are not necessarily evidence of ingestion via contamination, it could be due to Micro-dosing or the sample was taken after a significant period after a larger quantity was ingested.
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Present* not prevent
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What does the scientific literature tell us about the effects of super shoes on running economy and race performance? Let’s investigate.
Long thread 🧵
*** Disclaimer***
Without directly testing Assefa in the laboratory we can not determine the effect of super shoes on her running economy and other physiological markers. However, we can explore what the academic literature may suggest is possible and/or not possible. 2/
The first study to examine super shoes was Hoogkamer et al. (2017) pioneering paper. Here researchers observed an enhancement in running economy (RE) on average by 4% compared to traditional racing shoes.
The lower the mass of the leg further away from the body the lower the energetic cost to move it.
East African's have small amounts of musculature in the lower leg. Their gastrocnemius is small and the bulk of the mass more proximal to the knee with alimb ankles.
The gender gap exists across all running distances as shown by Thibault et al (2010) study showsthe smallest margin in running events of 6.5% in the 100m but the largest difference 13.96% I the 4x100m.
Both the rider in question who rode away and the group of riders in question regarding the nandrolone tests where both high natural occurring levels and contamination were ruled out were part of Shane Sutton's squad of riders.
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As Shane's squad under went testing for nandrolone in an unacredited WADA lab against WADA's rules as few as 10 British Cycling staff were aware, including the gang: Brailsford, Sutton, Peters and Freeman.
@WorldAthletics time for a periodic review of the DSD regulations which currently restrict 46XY female athletes who have testes & testosterone levels in the male range (7.7 - 29.4nmol/L) currently only restricting participation in events over the 400m-1500m.
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The performance benefits of testosterone do not discriminate between running distances.
On average males have a performance benefit of 11.2% (± 1. 25) across all running events & 19.0% (± 2.57) for all jumping events.
The gender gap exists across all running distances as shown by Thibault et al (2010) study showsthe smallest margin in running events of 6.5% in the 100m but the largest difference 13.96% I the 4x100m.