Why does pedaling up hill feels harder than walking up the same hill?
In: Physics
You’re comparing apples to oranges. The first one is you trying to lift you **and a bike** up a hill and the second is just lifting you. Strap the bike to your back and you’ll find walking up the hill far more tiring.
That’s assuming you’re in the right gear for climbing hills. The gears on your bike are a way to trade effort for distance. In higher gears, you get more bike travel for pedal travel, but you need to supply all the energy that travel will take. In a low gear, your ratio is about 1.2 to 1.5 to one. That means one downstroke of the pedals from top to bottom (half way around on the pedal) gives you 2/3 to 3/4 of a rotation of the wheel and about 1.5 meter/yard of travel. This is why low gear feels “floaty”. It far easier to move a bike that distance than to take a step, so your legs have a lot of spare strength that isn’t being used.
When you shift to the highest gear, you’re at about 4.5-5 to one. That’s great on flat ground where that one step on the pedal will move you 5.5-7.5 m/yd. At a fairly slow pace of one downstroke per second that works out to about 15mph/23kph. That’s about twice as fast as jogging for much less effort.
Going up a hill in high gear though means that one downstroke needs to supply all the energy to raise the bike over that greater distance. You’d struggle to jump that high with the bike on your back, and so you struggle on the pedals too.
Latest Answers