You would need to test it - but isn’t height squared likely to be a reasonable proxy for CdA? In which case it would absolutely make sense in that regard.
Given actually testing CdA is a lot harder than working out height squared.
I always have to explain to our TTT team on the Tuesday Zwift racing league that w/kg is essentially irrelevant on the flat… an alternative metric (w/drag) is much more useful, but harder to communicate.
We could add a Z-axis: Bench Press / Weight. Bench Press is mostly a useless move. Unless perhaps a boulder is on your chest. But it’s my favorite weight room move so it gets my vote.
Just for the academic argument, measuring “fitness” and determining what “fitness” is, is hard. That is likely why various fitness tests have multiple components. You need to pass all of them to be “fit” for whatever duty one is considering.
For cycling, I was at my best w/kg and best BMI with an FTP of 240 and a weight of 60 kg (height 5’8"). But in no way did I have good fitness and a healthy human life style going on. I could pedal a bike and that was about it.
Fast forward and I’m carrying a bit of extra weight today (2-3kg) but due to strength work and walking/hiking more in addition to cycling avidly, but consider my overall fitness to be much higher.
w/kg is IMO an over rated metric. As a smaller guy in the mid-atlantic race scene, I’d much rather have been 4 w/kg at 70-75kg than 4w/kg at 60kg. Sure I had a slightly easier time on hills and a CdA advantage. But we have a lot of flat riding and a lot of sprints so total watts matters. Or as they say in car racing: “There ain’t no replacement for total displacement”.
Back to the graphs, it does not appear to be a representative population sample (yet). That is not surprising given the forum. I have power data (or have coached) plenty of guys and gals in the 20-24 BMI range who are not at 4w/kg but ride and race avidly. 3.4 - 3.8 w/kg is a very popular power band in my experience. Suspect others here who help or coach riders can confirm this.
@maletero I have a W/kg below 3.0. It’s a bit embarrassing to admit it in the forum as mostly folks like to prop up their above average achievements. I assume that has something to do with it. If you are below average, you are likely not going to feel particularly comfortable “outing” yourself as a subpar performer in a thread like this; so, yes, I assume results will be weighted to the upside.
For sure. Heck, this thread was kicking around for a few days before I posted my stats. Self-selection here makes sense, especially since this thread has opportunity for double shaming—high BMI and low W/kg, for guys like me—but I’m surprised that it’s this far off.
Reluctantly, I did post, so I’m one of the two low dots in the middle of the graph… playing a bit of the anchor role so that line doesn’t go too high I guess… it’s a bit cold and lonely below that 3.0 w/kg line though
That’s like comparing weight between two people with a different height, a 90kg 170ck guy looks completely different from a 95kg 2m guy. So we developed BMI to compare them, BMI*W/m² does the same as BMI it creates an FTPI, functional threshold power index
I mean… it seems like just hunting a metric that feels better for a certain build. I haven’t found anything on this thread that convinces me that ftp/h^2 is a meaningful metric. We could also plot ftp/IQ or ftp/hours of sleep per night, but I don’t think it would be particularly meaningful
FTP correlates linearly with mass, right? And mass correlates linearly with height squared (that’s what the BMI formula tells us). Therefore FTP linearly correlates with height squared. Some riders want the biggest W/kg other riders want to be strong but also fit in other areas or just don’t like being lean all the time but we like to compare each other anyway. We usually use W/kg but that works for pros but not us because we have other goals but we still want to know who’s strongest, when you multiply bmi with W/kg you actually take mass out of the equation (it’s the same as FTP/h²) and now you can compare how powerful your legs are irrespective of height differences or if you carry excess upper body musculature or some extra body fat.