7 ms·

Every cyclist has a powermeter and the power is recorded. Why not require them to upload the power file directly after the race? Since they all ride the same co

Every cyclist has a powermeter and the power is recorded. Why not require them to upload the power file directly after the race? Since they all ride the same course, you can correlate power output with speed (taking riders height and weight into ac ount) to spot outliers. I know there's drafting, differently aerodynamic bike setups and other factors to consider, but in principle I guess a sudden 20 watt external power gain could be detected that way.

cheeze 2y ago
Would be trivial to fake the data
- karaterobot 2y ago
  How?
  - blakes 2y ago
    Things like this have been done before: https://www.dcrainmaker.com/2022/12/zwift-uci-cheating-astounding-championship-qualifier.html https://www.dcrainmaker.com/2022/12/zwift-uci-cheating-astou...
  - genedan 2y ago
    When I used a power meter, the data could be exported in some kind of machine-readable format like CSV. All you do is change the numbers.
- giobox 2y ago
  It wouldn't be that hard to mandate the riders use pedals that are only fitted at the course/track and otherwise stored by olympic officials. Power meters integrated in pedals have been a thing for a long time now: > https://www.garmin.com/en-US/p/658593 https://www.garmin.com/en-US/p/658593 It doesn't need to be pedals either - it could be a standard crank arm or any other easily accessible part that can effectively house a power meter. I'm sure there are plenty of other issues with this power meter based approach, but securing the data is probably doable to a reasonable degree.
  - rich_sasha 2y ago
    All these parts (pedals, cranks etc) are very much an integral part of precisely how you set up the bike, not so much things you swap out without noticing. You'd get pushback from the teams if suddenly you mandated a particular pedal or crank. Some racers are very particular about what pedals they want. And cranks aren't exactly roadside-replacable.
    - giobox 2y ago
      You can be assured the component manufacturers would happily sell "certified" gear, and lots of us would buy it imitating our heroes etc. The parts can be identical to the parts used in training. Said certified gear can meet the olympic standards for data integrity. The cycling industry adores selling "pro" gear to amateur customers and the associated markups (UCI approved!). This is not that different to amateur motor racing, where its expected you only bring a helmet that's certified by an external body (Snell/FIA etc). There are generally only a handful of pedals designs in use in the pro-peleton today, so not like we are talking about moving a mountain, and the UCI already regulate a lot of existing parts. As I said, I suspect this is not the main problem with this approach, there are likely many other much better reasons why this isn't a good idea.
heroiccocoa 2y ago
I wonder if we did a Fourier Transform of the power signal, would the 20 W appear in the DC bin as an anomaly?
rich_sasha 2y ago
I guess you wouldn't detect it. Elite cyclists can easily sustain 400-500 watts for many minutes, 20 watts is like 5% - a rounding error compared to variability of power input. The issue with drafting would be that it comes and goes. In a sprint finish, one moment you might be drafting, another trying to overtake the other guy (so not drafting), then fall behind again and draft, all in a matter of seconds. Then, there's the road gradient, also a massive impact on the power/speed function, and it's highly localized. You might know that a stretch of the road is 8% on average, over say 100m segments, but locally it can be much more or much less. On sharp switchback the inside of the corner can be 20+% when the outside is only 5-10%. Plex it's a race, power goes up and down in response to events, one moment you're sitting in a group, another you're chasing the guy in front. Presumably that's also where you'd press the boost button - when you'd legitimately be putting down more power. In amongst all that I doubt you would see an extra power boost.
- Aperocky 2y ago
  I think the only reason that motor doping is pretty much non-existent today is really because that it's useless unless it's a flat sprint stage. The battery and the motor would be significant weight to carry when it comes to the mountains, not to mention this deadweight must be carried all the way from start to finish and only be used for maybe 60 seconds.
  - throwup238 2y ago
    > The battery and the motor would be significant weight to carry when it comes to the mountains, not to mention this deadweight must be carried all the way from start to finish and only be used for maybe 60 seconds. Bikes have a minimum weight of 6.8 kg in UCI competitions and the lightest bikes are at least a kilogram lighter than the minimum, so they have to add weight anyway.
  - rich_sasha 2y ago
    Pro bike weights are already often below UCI minima (6.8kg IIRC), and ballast is added to meet minimum weight requirement. So I guess this could replace some of the ballast.
andix 2y ago
Isn't the powermeter usually measuring tension forces on the pedal arms? So it won't measure the forces of a motor which is probably inside one of the bearings.
- trillic 2y ago
  Exactly, it would show outlier performances where speed / pedal power ratio was too high in certain sections.
  - andix 2y ago
    This seems hard to do in my opinion. There are a lot of hard to predict factors, like aerodynamics (riding behind another rider takes much less power) and wind. Also the speed and power measurements are usually not extremely precise. There is a few percent of tolerance in most standard equipment. Exact GPS speeds are really hard to measure during cornering or in areas with limited visibility to the sky.
  - klyrs 2y ago
    So we need a power meter at the pedal and a power meter at the tire/road interface. And of course, you don't expect those values to agree due to mechanical inefficiency. Which means that even with that level of scrutiny, there's a few percentage points of overhead for your motor-dopers to play in.
Jean-Papoulos 2y ago
- The number of ways data could be faked is frankly staggering - Drafting is huge - Since drafting is huge, to win you often have to just "unstick" the rider behind you from your wheel, then stay on his pace for the rest of the distance. So you only need a very short burst (10-15s of effort) where a few watts will make a great difference. That's hard to detect. - In a climb, everybody will ride differently (different lines, levels of power) due to body shape, current objective, available draft, etc... You end up with insufficient data to reach the level of certainly that would be needed to accuse someone of motor doping Overall, it's just simpler to just scan all the bikes.
2716057 2y ago
One can tamper with the data or the power meter itself. If a cheater is faster than a competitor pushing more watts, his team will respond with the usual BS: the bike's aerodynamics, stiffness and its super-innovative tires made him faster... However, mandatory power recording could become quite valuable over the long run. The peloton should be large enough to allow data scientists to detect the abnormalities (unless all the teams reach an agreement to cheat consistently ;)). Once a history is built over a decade or longer, "unphysiological" power output could be detected quite easily.
ertgbnm 2y ago
The problem is that Olympians are kind of just by definition outliers. Is this competitor a cheater because he can sustain 20 watts higher than others for most of the race? Or is he just a physical outlier who made it to the Olympics because of his unusual power output?
- Cpoll 2y ago
  > sustain 20 watts higher This would theoretically detect the opposite. The power meter (on the crank arm) detects force applied on the pedal. The discrepancy would be if they're overtaking other racers pedalling the same wattage.

cheeze 2y ago

Would be trivial to fake the data

karaterobot 2y ago
How?
- blakes 2y ago
  Things like this have been done before: https://www.dcrainmaker.com/2022/12/zwift-uci-cheating-astounding-championship-qualifier.html https://www.dcrainmaker.com/2022/12/zwift-uci-cheating-astou...
- genedan 2y ago
  When I used a power meter, the data could be exported in some kind of machine-readable format like CSV. All you do is change the numbers.
giobox 2y ago
It wouldn't be that hard to mandate the riders use pedals that are only fitted at the course/track and otherwise stored by olympic officials. Power meters integrated in pedals have been a thing for a long time now: > https://www.garmin.com/en-US/p/658593 https://www.garmin.com/en-US/p/658593 It doesn't need to be pedals either - it could be a standard crank arm or any other easily accessible part that can effectively house a power meter. I'm sure there are plenty of other issues with this power meter based approach, but securing the data is probably doable to a reasonable degree.
- rich_sasha 2y ago
  All these parts (pedals, cranks etc) are very much an integral part of precisely how you set up the bike, not so much things you swap out without noticing. You'd get pushback from the teams if suddenly you mandated a particular pedal or crank. Some racers are very particular about what pedals they want. And cranks aren't exactly roadside-replacable.
  - giobox 2y ago
    You can be assured the component manufacturers would happily sell "certified" gear, and lots of us would buy it imitating our heroes etc. The parts can be identical to the parts used in training. Said certified gear can meet the olympic standards for data integrity. The cycling industry adores selling "pro" gear to amateur customers and the associated markups (UCI approved!). This is not that different to amateur motor racing, where its expected you only bring a helmet that's certified by an external body (Snell/FIA etc). There are generally only a handful of pedals designs in use in the pro-peleton today, so not like we are talking about moving a mountain, and the UCI already regulate a lot of existing parts. As I said, I suspect this is not the main problem with this approach, there are likely many other much better reasons why this isn't a good idea.

heroiccocoa 2y ago

I wonder if we did a Fourier Transform of the power signal, would the 20 W appear in the DC bin as an anomaly?

rich_sasha 2y ago

I guess you wouldn't detect it. Elite cyclists can easily sustain 400-500 watts for many minutes, 20 watts is like 5% - a rounding error compared to variability of power input. The issue with drafting would be that it comes and goes. In a sprint finish, one moment you might be drafting, another trying to overtake the other guy (so not drafting), then fall behind again and draft, all in a matter of seconds. Then, there's the road gradient, also a massive impact on the power/speed function, and it's highly localized. You might know that a stretch of the road is 8% on average, over say 100m segments, but locally it can be much more or much less. On sharp switchback the inside of the corner can be 20+% when the outside is only 5-10%. Plex it's a race, power goes up and down in response to events, one moment you're sitting in a group, another you're chasing the guy in front. Presumably that's also where you'd press the boost button - when you'd legitimately be putting down more power. In amongst all that I doubt you would see an extra power boost.

Aperocky 2y ago
I think the only reason that motor doping is pretty much non-existent today is really because that it's useless unless it's a flat sprint stage. The battery and the motor would be significant weight to carry when it comes to the mountains, not to mention this deadweight must be carried all the way from start to finish and only be used for maybe 60 seconds.
- throwup238 2y ago
  > The battery and the motor would be significant weight to carry when it comes to the mountains, not to mention this deadweight must be carried all the way from start to finish and only be used for maybe 60 seconds. Bikes have a minimum weight of 6.8 kg in UCI competitions and the lightest bikes are at least a kilogram lighter than the minimum, so they have to add weight anyway.
- rich_sasha 2y ago
  Pro bike weights are already often below UCI minima (6.8kg IIRC), and ballast is added to meet minimum weight requirement. So I guess this could replace some of the ballast.

andix 2y ago

Isn't the powermeter usually measuring tension forces on the pedal arms? So it won't measure the forces of a motor which is probably inside one of the bearings.

trillic 2y ago
Exactly, it would show outlier performances where speed / pedal power ratio was too high in certain sections.
- andix 2y ago
  This seems hard to do in my opinion. There are a lot of hard to predict factors, like aerodynamics (riding behind another rider takes much less power) and wind. Also the speed and power measurements are usually not extremely precise. There is a few percent of tolerance in most standard equipment. Exact GPS speeds are really hard to measure during cornering or in areas with limited visibility to the sky.
- klyrs 2y ago
  So we need a power meter at the pedal and a power meter at the tire/road interface. And of course, you don't expect those values to agree due to mechanical inefficiency. Which means that even with that level of scrutiny, there's a few percentage points of overhead for your motor-dopers to play in.

Jean-Papoulos 2y ago

- The number of ways data could be faked is frankly staggering - Drafting is huge - Since drafting is huge, to win you often have to just "unstick" the rider behind you from your wheel, then stay on his pace for the rest of the distance. So you only need a very short burst (10-15s of effort) where a few watts will make a great difference. That's hard to detect. - In a climb, everybody will ride differently (different lines, levels of power) due to body shape, current objective, available draft, etc... You end up with insufficient data to reach the level of certainly that would be needed to accuse someone of motor doping Overall, it's just simpler to just scan all the bikes.

2716057 2y ago

One can tamper with the data or the power meter itself. If a cheater is faster than a competitor pushing more watts, his team will respond with the usual BS: the bike's aerodynamics, stiffness and its super-innovative tires made him faster... However, mandatory power recording could become quite valuable over the long run. The peloton should be large enough to allow data scientists to detect the abnormalities (unless all the teams reach an agreement to cheat consistently ;)). Once a history is built over a decade or longer, "unphysiological" power output could be detected quite easily.

ertgbnm 2y ago

The problem is that Olympians are kind of just by definition outliers. Is this competitor a cheater because he can sustain 20 watts higher than others for most of the race? Or is he just a physical outlier who made it to the Olympics because of his unusual power output?

Cpoll 2y ago
> sustain 20 watts higher This would theoretically detect the opposite. The power meter (on the crank arm) detects force applied on the pedal. The discrepancy would be if they're overtaking other racers pedalling the same wattage.