Was Chris Froome Doping? A Data-Driven Perspective | Hacker News Reader

Was Chris Froome Doping? A Data-Driven Perspective

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34 pointsaabessman14 comments

I listened to Sallet's interview on iTV4. He claimed three possibilities (paraphrased) 1) Unique physiology, 2) drugs, 3) mechanical enhancements. Sallet failed to mention 4) wrong inputs to the model. When the interviewer challenged him on that, his retort was that his model was correct.

I find it ironic that both Sallet and Armstrong benefit from doubt on Froome's performance - as it validates their own agendas.

Though, perhaps Sallet got it right with 1) The two leaders in the tour grew up training at high elevations. Perhaps, the next wave of cheating will involved epigenetics. I expect the 2035 TdF to be highly suspect.

[Edit spell correction]

> 4) wrong inputs to the model.

And a wrong model. There're a lot of calculators out there, e.g. [1]. Some more, some less sophisticated. But they all provide rules by thumb at best.

It starts at the mechanical losses, rolling resitance and aerodynamics (it's often neglected on calculations regarding climbs). Does his model take wind into account?

[1] http://www.kreuzotter.de/english/espeed.htm

Interesting link. What? No entry for time spent out of the saddle? How much drafting? What brand of rims? Tires? Beard?

Perhaps measuring direct inputs would be better.

I notice that the kreuzotter model was tested with SRM cranks. I wonder if a universally applied power meter for all riders would work? Somewhat akin to the Dimension Data GPS trackers attached to the rider's seats, this year. If everyone has one, then it is an even playing field.

The problem is getting an accurate strain gauge that would work for different bikes, pedals, shoes. Plus, be consistent enough to not yield false data, given weather, crashes, mechanicals, and whatnot.

Thank you, this is a very sound approach for estimating the power to velocity relationship. Actually, it's the by far most sound approach around. One general remark though: It is important to only include measured power data which is indicated by a little flash on Strava. Strava always shows power data, but otherwise estimates. Most riders use similiar devices (SRM, Quarq, P2Max), so the numbers are comparable within about 5 %.

I really hate, how convicted dopers like Armstrong and Jalabert defame Froome. After all Froome is not convicted. If people like him or not.

With all the speculations, we are not to forget that training methodology has evolved immensly over the last couple of years. And Chris Froome is actually more at 65 kg then at 67 kg.

Lastly, unfortunately mankind cheats. It's in our nature. Businesses are bribing, countries are spying, Fifa, well ... (be sure similiar however probably on a much smaller scale things happen at the IOC), students take beta blocker and ritalin. CEOs tell so many lies and intimidate so many people on their way to the top. Cheating is everywhere, we all did it in smaller or larger ways.

Apparently Froome lost some of his doping as Quintana completed yesterday's final ascent 30 second faster than him (sarcasm directed to Sallet). Still some fans were angry with Froome and were visibly happy to see him lose ground. People should be innocent until proved guilty also on a bike and tv pundits should be cautious about what they say.

A fan was caught on TV spitting directly at Chris Froome yesterday. The hysteria that armchair power analysis 'experts' and irresponsible pundits have whipped up is disgraceful.

...leading to a 6.13 W/kg. [Sky] also claim that their chain rings hamper the measurement of power by 6%, and give 5.78 W/kg to account for this.

I can't think of any set of facts that would make this adjustment make sense. Can any mechanical engineers help?

I doubt Shimano will be happy if Jean-Louis Talo starts claiming that it was his weird elliptical chain ring that turned a 5.78 W/kg loser into a 6.13 W/kg champion.

Presumably the chainring losses are roughly similar for every rider which is why no-one complains about them. Around 6% seems plausible when you remember that for cars crank horsepower is usually 15% higher than wheel horsepower. Transmission losses are an unavoidable cost.

TFA with its 6.06 W/kg estimate is talking about power at the wheel, because it's using Strava rather than e.g. PowerTap data. (Although Strava claim to account for "rolling resistance".) By making the adjustment Sky seem to be claiming that Froome's equipment wastes less power than everyone else's does. Again, if they spell that out, Talo will be happier than Shimano, their nominal sponsor.

Crank and pedal based power meters usually dont give accurate power readings when used with oval chainrings.

Quick googling suggests Team Sky still use Stages as a power meter, and Stages say on their website: "Through our own testing, and using a hub-based meter as a control, we conclude that there will be a 4-5% increase on the readings from a Stages Power meter when used with a non-round chain rings." [1]

[1] http://support.stagescycling.com/support/solutions/articles/...

Today a friend on a social network floated an interesting hypothesis when the topic of the recent spate of citizens dying while engaged with law enforcement officers came up.

He suggested that there might be an underground practice of juicing among law enforcement officers (to gain a strength advantage on the job) and that what we're really seeing is occurrences of "roid rage".

Anabolic Steroid Use and Abuse by Police Officers: Policy & Prevention http://www.policechiefmagazine.org/magazine/index.cfm?fuseac...

Cops’ Use of Illegal Steroids a ‘Big Problem’ http://www.infowars.com/cops-use-of-illegal-steroids-a-big-p...

Cops on Steroids http://www.menshealth.com/health/scandals-cops-and-steroids

Steroid Abuse by Law Enforcement Personnel http://www.deadiversion.usdoj.gov/pubs/brochures/steroids/la...

Police Juice Up on Steroids to Get 'Edge' on Criminals http://abcnews.go.com/US/story?id=3745740&page=1

Dopers in Uniform: Cops on Steroids https://thinksteroids.com/articles/dopers-uniform-cops-stero...

Steroid abuse major problem among police officers http://taylorhooton.org/steroid-abuse-major-problem-among-po...

Chief constable admits police officers across UK 'are using criminals to buy steroids and abuse their power for sexual gratification'

From the Men's Health article linked above:

"Officer Jimmy sees the matter differently. Although he professes to feel conflicted about juicing--it is, after all, a felony to take anabolic steroids without a prescription--he thinks 'roids made him a better cop. "What law enforcement needs is a little testosterone," he says. "Every cop should do a cycle a year."

Yeah, Jimmy. What could possibly go wrong with that idea?

This isn't new. I knew a couple of cops who used to attend an MMA gym. They were yoked and everyone in the gym figured they juiced. Things like the Rodney King beating are a lot more understandable when seen as Roid rage.

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