The Hour Record

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  • Wonder where the gains from thinner air begin to be be outweighed by the lack of oxygen? Mexico City used to be the place for the record back in the day and that's a good 350m higher than Aguascalientes. Then you've got Cochabamba in Bolivia sitting another 300m or so higher at 2,560m. I'd imagine the logistics of an hour record attempt in Bolivia are a bit more challenging than Mexico though and that's why we're not seeing attempts made there.

  • there's a lot on that idea here­s/project-3-59-completed-it

    *When you go to altitude a number of things happen that both positively and negatively impact upon performance. The first thing that most cyclists know is that altitude reduces air density. This happens because the barometric pressure reduces as altitude increases. Air density linearly impacts on aerodynamic drag power, so a 10% lower air density means 10% less aerodynamic drag power. This is great for a cyclist as aerodynamic drag power is the biggest power loss of the entire system, around 90% of total drag for Ashton's IP. At the 2020 World Championships the air density was 1.155kg/m^3. At Aguascalientes during Ashton’s ride the air density was 0.932kg/m^3. A very welcome drag reduction at 62kph of around 70 Watts.
    However, this isn’t the entire story. The reduction in barometric pressure also reduces the partial pressure of oxygen, meaning aerobic power reduces significantly. Ashton is fairly well acclimatised from his time spent at the USAC altitude training facility in Colorado Springs but power losses at altitude vary significantly between athletes. Based upon Basset et al 1999 study in to aerobic power drop off at altitude, we can expect to see a 7.5% reduction in aerobic power at Aguascaliantes for acclimitised athletes, and 11.5% for non-acclimtised. Based on our experiences with elite athletes, these aerobic power drop offs can vary from 2 to 20% in practice. If we take the 7.5% drop off, this equates to around a 27 Watt loss of power.
    The next effect isn’t too well documented but is very meaningful. CdA is not a stable constant across altitude. It's something we investigated heavily alongside HUUB & Vorteq in our involvement with the HUUB Wattbike altitude project. Without going in to the deep science, riders get draggier at altitude through no fault of their own. The effect is very rider specific, however we can make some good calculations based on tests we’ve previously conducted. Going from sea level to Aguascalinates would have increased his CdA from 0.159m^2 to around 0.1655m^2, a 4% increase or around 15 Watts more aerodynamic drag.

    We need to also account for the impact riding solo on a track has when compared to a ride in competition where a well-timed catch can save significant time due to the reduction in aerodynamic drag. This effect is variable depending on the size of the rider you are catching, the speed difference and how long you spend in the draft, however from our own studies on the velodrome a typical catch is worth around 0.003m^2 CdA reduction over a 4km individual pursuit, or 7 Watts in power terms.*

  • I don't think he'll be able to do it, seeing as Campenaerts also set it at Aguascalientes. But @umop3pisdn will be the person to confirm this.

  • He'll beat it by 15 metres, then be popped for doping.

  • Plot twist!

    But he needs stuff to thicken his blood...

  • The record is currently held by Belgium's Victor Campenaerts, who rode 55.089km last December in Manchester.

    I'm sure there'd have been a bit more fuss around here if that was the case.­4574

  • More BBC fake news

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The Hour Record

Posted by Avatar for hippy @hippy