Torque, one of the most overlooked parts of training with a power meter. So what is torque? Torque is a twisting force that causes rotation. So torque is a force, and force is measured using Newtons or kilograms per square. So what then is power? Power on bicycle is essentially, the frequency you can exert the torque to the pedals. Understand?
Here is a practical example you can understand. Lets say you are riding up a hill and you don’t have a power meter but you can measure your speed. So lets say you are climbing this hill at 20km/h, but you are riding you 53T chainring in front and your 28T rear cog. The torque you are pushing is lets say 30Nm and power is 280W, cadence 65RPM (please, these numbers are not accurate and only serve to illustrate). So 20km/h@280Watts (30Nm torque factor). Lets say you are now finding your legs are burning, so you drop the chain into the 36T chainring in front, you immediately see that you have increase you leg speed (cadence) to maybe 100RPM just to maintain the same speed. So what happens to the power and toque readings? Well the torque factor reduces because of the gear ratio you are using, and the power increases because of the cadence. The torque is reduced because of the lighter/easier gear, but the frequency you pedal at, the cadence, is much higher, so this makes up for the torque loss. How is this helpful to my riding? Well, if you figured out, that riding a higher torque at a higher frequency gives you more power, you are right. In real terms it means, if you can ride the hardest gear you have at the highest cadence around, you will produce loads of power. So is this possible? Yes and No, the question is, for how long?! So how long then? That question is so individual to each person, the parameters that govern that question include: Current Fitness, strength, lung capacity, VO2 max potential, body morphology and so on. So what am I trying to say here?
Have you seen Chris Froome ride mountains? If you have, you’ll know he as an incredibly high cadence. But he is a skinny runt. If you know what Peter Sagan looks like you’ll know he is bulky and well built, and you can tell he can push out more power, so why then can Froome out climb him? Sagan has more muscle, surely he can push more torque in a harder gear than Froome? Well because Froome has a freakishly high VO2 max (genetic) and a Higher Latactate Threshold, he can work hard for longer than Sagan although at lower torque, but with higher frequency. Remember Power is, torque plus frequency. So Froome moves less torque faster than Sagan can move higher torque slower. Add into this equation now that there is a 10 kg weight difference and Froome floats up a climb faster.