Nate's ideas about W/kg and size

Unless the CdA is a big enough difference as we’ve said. Neither Ollie nor Alex are Clydes. They should have done it with Mannon and Connor as well :smiley:

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Yeah, there must be another crossover point ie where the cda difference and/or the gradient is steep enough. But we don’t know where they are either, or if its even within the window of a cyclable climb :smiley:

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Yes and Connor’s giant bike, shoes and clothes would scale heavier as well, narrowing or possibly removing the system weight advantage :rofl:

For me, I’m ALWAYS at a disadvantage because I’m small (172cm, 67kg) and I have a heavy bike (10kg). So I have to make up for it with tenacity :sweat_smile:

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Yeah I feel like we are brothers in arms at opposite ends of the spectrum :rofl: Even getting down to 80kg would do me.

I did feel sorry for the 43kg lad at the crit on Saturday :rofl:

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I think most of us who are in tune with our bodies, know the range of weights where we feel great and ride at our best, given the training we are able to do. I certainly don’t feel like bulking up based on this discussion :joy:

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Deej covered it for me, and note that I put heavy in quotes for a reason. Yes, among TDF winners, they are on the heavier side. I would also add in Merckx

Here is my point:

I would argue there is a minimum w/kg needed to win the tour, and that there is a soft upper limit to weight in which that w/kg is acheivable. (if min w/kg = 6.3, then someone at 80kg would need ftp of 504). This would imply that among the people who have the min w/kg, they fall under a specific weight. This further implies that there is a weight limit that needs to be hit to win the tour as well. If these assumptions are true, then the weight range for people who can win falls between 45kg and 80kg (technically I think the top end range is probably closer to 75, but big mig kind of refutes that unless the required w/kg in those years was reduced).

When you look at the weight of winners in comment 130, it appears that repeat winners are more likely to be closer to the top of the range range than the bottom of the range. This is what I am referring to as “heavy” - being closer to the theoretical upper limit of weight. It makes sense that people who hit the min w/kg at a higher weight will be more dominant given the science discussed in this thread.

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Yep. For me…my realistic range is confined within 165-185. It’s been decades since I’ve been at thr bottom of that range, but I very rarely exceed the top end. The math on this is easy for climbing. What I’m genuinely curious about, is how, say, 20 pounds affects things on a cross course.

Even the math for accelerating out of corners and off the gun is easy. But what about mid corner? Suspension losses? Traction? I couldnt even really venture a guess, other than dropping 20 lbs mid season and seeing how i fare in races…

I almost feel like this is a conversation to be had with someone that sets up race motorcycles.

Poorly, you will fare poorly

Lol, yea I’m sure that would be the case if I dropped it over 6 weeks in between races in the fall.

A more realistic thing is dropping 15-20 pounds between now and October, which is a very reasonable proposition. But of course if my power is up vs last year…the comparison goes out the window.

But in order for this to be valid you’ve got to know the denominator. If the vast majority of TDF riders fall into the 45-80kg range (and I suspect they do). Then it stands to reason it’s highly probable that winner will come from that pool. But what sets the winners apart? If lots of riders in the 45-80kg range in the tour aren’t even coming top 10. Then it’s not weight that is the deciding factor.

What is it about their physiology that enables them to win, and in some cases repeatedly?

Jeezus wept.

BT summed it up nicely.

Rolling resistance is a larger percentage of a smaller riders overall power. Dramatically so, on very rough terrain. Poor chip seal, cobbles etc. The rougher the terrain, the greater the advantage of the larger more powerful athlete.

System weight vs gravity is also a larger percentage of a smaller riders overall power. The lighter the rider, the greater the penalty. System weight is significantly more important for very light riders. In weight restricted racing. UCI 6.8kg limit. It penalizes very light riders, assuming the manufacturers actually made bikes that hit the weight limit.

Mechanical resistance is a greater percentage of the smaller riders total power.

Pogacar is not 55kg. He’s 65kg.

This is one of the most miss understood variables. Often people use riders like Pogi, Remco etc as an example of why light riders have aero advantages etc.

It’s wildly inaccurate.

A flat TT is w/cda.

Yes, the smaller rider will have a lower cda. However, due to allometric scaling, the equal strength larger rider will generally travel faster. If… this is the important bit. They are doing the same w/kg. Which they are often not.

Let’s take Stefan Kung vs Remco.

Both are fantastic TTers. They often match or come close to each other in most TTs.

Stefan Kung is 193cm 83kg
Remco is 171cm 61kg

In a typical TT,
Remco is doing 400w. 6.5w/kg.
Stefan is doing 470w. 5.6w/kg.

Which is why, when they hit a sustained climb, even with the slight overall percentages disadvantage to the smaller rider, Remco drops Kung like a hot potato. Because in pure w/kg they are not remotely the same.

What we are watching is the allometric scaling at work in real time. Kung’s far larger muscle mass vs his less penalized frontal area, allows him to compete with, by pure w/kg, a far stronger rider. (frontal area is squared, muscle mass is cubic)

Hence why, ‘generally’ the absolute freaks that are GC riders are able to compete with the far larger and more powerful TT specialists. Kung, Ganna, Bissegger, etc

What you are not watching is an actual even w/kg test.

That’s what we’re watching when a climb is steep enough and long enough. Even with the percentage disadvantages of being light. Generally, lighter riders are able to reach higher pure w/kg.

It’s no surprise that the strongest riders on Earth by pure w/kg metrics. Remco, Pogacar, Vinegaard are able to excel at all disciplines. They are literally putting out the most power vs weight of any cyclists alive.

Now, if an 80kg rider was able to reach 6.5w/kg 520w FTP, they would obviously win everything.

So far, this hasn’t been possible. I don’t believe it actually is, without extreme drug enhancements.

The reasons many have missed here, is absolute energy ceilings. It seems that humans are rate limited in our ability to generate energy from glycogen and fat. Currently, the best trained athletes are maxing out at 430-470w, regardless of size. Our bodies simply cannot generate enough energy in a sustained manner to go much beyond this.

This, combined with aspects of cooling and fueling such tremendous energy use puts larger riders at a disadvantage. Particularly over longer events, with sustained high power.


What a fascinating and insightful read. Thanks for putting in the time to write that. :slightly_smiling_face:


Taking these numbers in conjunction with the findings posted by RChung, although Kung weighs 36% more, his CdA is probably only about 0.7x36% or 25% more.

So, although Remco has a 16% w/kg advantage, he only has a ~6.4% W/CdA advantage.

Not sure how much Kung’s rolling resistance advantage overcomes this gap, but the example shows how riders with different mass, watts, and drag can be closely matched.

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Great summary :clap:

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How about wearing a weight vest of 10kg for every other race? This would eliminate some impact of change of fitness over a season.
Imperfect, as it wouldn’t scale your size and therefore CdA quite right compared to a well-distributed sprinkling of lard.

Hmm yea, that would do it haha. Now the question is how much do U care about winning lol…

Actually…a better way…and this might actually be kind of realistic…is just go by rpe on 2 different practice laps and compare times.