Watts and speed

Hi all

I have a discussion with my friend.

Example: 2 men, same weight, rode the Ventop route in exactly 90 minutes. So they rode the same speed.

BUT: Man 1 rode with a much bigger gear (50-16) than man 2 (34-14). My friend says they delivered the same amount of watts but I doubt that because man 2 had an much higher cadance… So I believe man 1 produced a lot more watts (power).

What are your thoughts here?

They produced the same average wattage.

What about the difference in cadance? Man 2 pedals much faster to meet the same speed…

They can have a difference in cadence but still produce the same wattage.

Somebody will be along soon to explain it in full detail.

Power (Watt) is the force on the pedal times cadence.

Power = Force x Velocity

So you can produce the same power with a high force(torque) and low velocity (cadence), or a low force and high velocity.

If you pedal up a hill in a high gear you’ll feel it is much harder. That the greater force. Someone else spinning the gears in a low gear will feel a lower force, but they’ll apply it faster.

Power = Torque x Angular Velocity

Person riding in a bigger gear (but lower cadence) put out more torque, but lower angular velocity. Less RPMs @ More Newton Meters = More RPM @ Less Newton Meters.

Two similarly sized people getting to the top of a hill at the same speed, the average amount of power has to be (pretty much) the same.

There is no getting around this. And, trust me, cyclists have been dealing with this reality for a pretty long time.

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Assuming no drafting. With drafting, the wattage could easily be different, even on a hill.


Thx for the clear answers.