There is this french website[0] which (among other things) analyses TdF performances over the years.
They compute power metrics based on climbing times in the mountain stages. The trend these last few years is quite worrying, reaching and going above peak doping-era performances [1].
The website is maintained by a former pro-level coach of the festina era.
[0] https://www.cyclisme-dopage.com/
[1] https://www.cyclisme-dopage.com/actualite/2025-07-26-cyclism...
However, these year-by-year comparisons often miss a few key points...
- Technology advances. Looks at the jerseys worn during the peak doping era (Lance, etc) vs today - they look downright baggy in the 90s vs now. The bikes are more aerodynamic as well. The tire roll faster.
- Nutrition has changed MASSIVELY in the last ~5 years. Gone are bananas and pastries (even from the Italian and French teams). The "bonk" is almost completely a thing of the past at this level - cyclists are consuming carbs at rates that would have put most people on the toilet a few years ago. Part of this is better mixes; part of it is humans can simply consume more carbs than we thought possible (with appropriate gut training).
- Training itself has changed. It's year-round, it's far more structured. Everybody has a power meter, glucose monitor, etc. Kids are starting this structure training at younger ages.
Anyway, do I think pro cycling is 100% clean? No, of course not, there's massive incentive to cheat. Do I believe the top cyclists (Pogi, Vingegaard, etc) are clean (per current rules)? Yes. They're testing far too often to not be. Are they possible pushing the limits of what's legal? Probably (see also: CO training last year, which is now banned).
I'm trying not to pick sides but here are a few arguments they oppose to these key points :
- Technological advancement : Although it does play a role, they measure power in long climbs to limit that bias. Speeds are lower so aero plays less of a role. Bikes were already as light or even lighter in the 2000s. They also calibrate their power predictions against riders of the peloton who publish their power on strava.
- Nutrition has indeed changed, it helps producing near max power efforts at the end of long stages (aka durability) but doesn't play a direct role on pure max power (VO2 max related) which is what they are worried about.
- Regarding training, I'm not really sure, I think the pro peloton already had access to power meters in the 2000s.
- Regarding testing, it's indeed quite frequent but it's not bullet proof.
- I think the history of the sport is so bad it's hard to see the half full glass.