Originally Posted by
nslckevin
In real life performance it makes a huge difference if you’re 100kg and lean vs. 100kg w/ 20kg of excess fat.
That said…. To me, 300w for an hour at 100kg w/ 20kg of fat is much better than the same power for the lean 100kg guy. Internally I always think of my w/kg in terms of race weight. If I gain 5-10 lbs in the winter and I’m putting out good raw watts I don’t care that the w/kg number of lower than it could/should be. I know by the POWER that my fitness is good. The w/kg number is more important when it comes to going uphill of course, but if I’ve got the power in my legs I can lose a few lbs. and then go uphill fast.
It would be worth it for you to head over to the road or training forum on here to find the topic "why does 240w not always equal 240w" where a guy was lamenting how much power it was to go around a pan flat nicely paved bike track loop at 22mph.
It boiled down to the person probably being larger and more of a parachute. Larger is more CdA and more cost from rolling resistance. Larger riders punch bigger holes for smaller riders to rest behind. Smaller riders punch smaller holes that if a larger rider is following one, it can be less of a rest than desired.
Even in the flats there's a quite tangible penalty to larger riders. Accelerations in the flats cost larger riders more than smaller riders also.
Unless someone is pretty good at bikes, like a Cat 3 or faster, I doubt they can drop pounds AND hold power at the same time on command. I don't find that realistic for a hobbyist cat 3/4/5. I find it more realistic they stay within 5 pounds of whatever discipline weight they want to target.
All that to say, a 300w hour ftp on a 100kg rider isn't remotely the same even on flatter terrain as a 300w hour ftp on a 70kg rider. I don't race with pros that are combos of 60kg Colombians and 75 to 80kg Gannas. So the power delta on the flats doesn't ever seem to play out that way.