Originally Posted by
gregf83
Sorry, but there's no magic gains in efficiency here. You could pedal a perfect circle with uniform torque throughout a pedal revolution and it won't make you any more efficient. Efficiency is defined as energy out/energy in. This is easy to measure in a lab and it's been done many times. Pulling up or modifying your pedal stroke isn't any more efficient than pedaling the way most people do which is to exert maximum torque when the pedal is at 3 o'clock and unweight the pedal on the upstroke.
If you are generating more power by changing your pedal stroke you will also be burning more calories. Which isn't a bad thing but it's not more efficient by any conventional definition of the word.
You're not considering how the human body works though. Think of it this way... Let's say you are riding a hand pedaled bicycle. Instead of using your legs, you're using your much smaller and weaker arm muscles (for most people anyway). Now, if you tried to go the same speed as you normally would on a regular bike, you'd find it very difficult and you'd tire more quickly. This is because those smaller weaker muscles will start working anaerobically, which is much less efficient (energy in/out). So, the muscle groups you utilize affects your speed and level of exhaustion. The more muscle mass you use, the less exhausting riding will be at any given speed. If you use only your quads to push down, you'll get more tired going the same pace than if you use quads, hamstrings and glutes, etc