Thigh Master

When one calculates watts per kilogram. Is the mass only the weight of the rider without clothing, etc.? Or is it the combined weight of rider, their clothing, bicycle, tools, water bottles, etc.?

PeteHski

If you are using it for measuring your fitness then I would just take your undressed weight.

datlas 

Your body weight as above.

eduskator

Body weight! The rest (bicycle, clothes, etc) is pretty similar from a rider to another.

MoAlpha

Before or after pooping?

datlas 

For your ego, after.

For Zwift, before.

MoAlpha

I'd have to eat pig iron to get back into the Ds.

TMonk

Wake up, coffee + banana (maybe a small pastry portion), bowel movement, scale, kit up, then on the bike!

RChung

Depends on whether you're interested in the supply side or the demand side.

For supply side, just you, nekkid, post-poop.

For demand side, you, all your kit including water bottles, and your bike.

I would say that most people most of the time mean supply side.

blacknbluebikes 

do you want a bigger number or a smaller number? yes, you can pick, we won't tell anyone.

Bah Humbug

I usually think of it as a trait of the rider, so it's just the rider. Your W/kg doesn't change when you change bikes. And as mentioned, since most bikes are only marginally different in weight when accounting for the bike + rider system, it only matters in very narrow circumstances.

terrymorse 

Bike weight difference may have a marginal effect for a 100 kg cyclist, but it is more significant to a 60 kg cyclists.

If you're trying to estimate how fast you can climb a steep road, you'll be looking at the W/kg of the whole package (rider + bike + accessories).

Bah Humbug

Right, but my point is that in that case, the difference between a mid-range and high-end road bike is still very small compared to even a 60kg cyclist, and with two 60kg cyclists the FTP difference is likely larger than the bike weight.

PeteHski

Models that estimate how fast you can climb usually have separate parameters for bike and rider weights. If someone says they have a 4 W/kg FTP they are not including the weight of their bike and kit. Your power in terms of W/kg should be independent of what bike you are riding if you are comparing the performance of riders.

choddo

Soooo I don’t mean to be controversial but isn’t w/kg usually a measure of strength and fitness? If you make your bike lighter or leave a bidon at home, did you get stronger or fitter?

terrymorse 

The weight difference between a high-end climbing bike and a mid-range road bike is not very small. A decent climbing bike is easily 2 kg lighter than a mid-range bike.

PeteHski

Exactly. When discussing W/kg as a measure of human performance it is literally Watts per kg of bodyweight. The weight of the bike and kit is only relevant in cycling simulation models.

wheelreason

Really? So if your plump girlfriend is sitting side saddle on the toptube then does.... Oh never mind....

merlinextraligh

Fat bottom girls make the rockin world…

eduskator

Remember to go to the LOO before weighing yourself too! It helps to increase your W/KG.

Trsnrtr

I think that's backwards.

rsbob 

I prefer going to the loo frontwards, but to each their own.

Trakhak

Improved watts/kg value = higher watts or lower weight or both.

Trsnrtr

yep. Math brain fart.

eduskator

Easier said than done, though! Especially when you've got no more fat left to burn

I've been trying to squat and deadlift harrrrrd at the gym, but it would seem like mahhhhh legs just don't want to grow!