Originally Posted by
Carbonfiberboy
I don't have to guess what my legs are doing for three reasons - one, I do a lot of one-legged pedalling on my rollers and know exactly what it feels like to keep a steady rim rpm; two, when pedalling with both legs I can feel the muscles contract, driving the pedals; and three, as I said, I can pedal with hams alone so I know I'm not powering on the downstroke.
The funny thing about your second graph is that the black, "average" line is obviously software generated and does average the power output, but over a much longer term than the individual pedal meters. Looking at the graph, one can see that both pedals drop to zero power at the same time, yet the black line doesn't move. It should also drop to zero power if it's showing what you think it's showing. There is simply no other way to interpret the second graph.
My pedalling looks exactly like the second graph when I stand, but when I sit it looks like the graph I created for my post. I'm definitely not alone in my pedalling style! I ride with many people who can pedal circles. It's easy to tell: the upper body never moves on a rider who is putting a constant torque on the bottom bracket. Riders who bob or move from side to side under heavy effort are applying torque as shown by your graph. Something to do with Newton's laws of motion, I believe. I can climb at cadences down to about 45 without moving my upper body. Below that, I have to start pushing down hard and do bob.
The first graph is a clear demonstration of what I'm saying! Look at that cadence bounce with the change of pedal angle! When I pedal rollers, i.e. almost no averaging from momentum, the rollers make a constant noise. My cadence does not vary with pedal angle, which is what I'm talking about. So when riding in the saddle, no momentary accelerations.
Your "scientific" graphs, while undoubtedly accurate, are based on the pedaling of an unknown person, of unknown ability. We don't even know if they were sitting or standing! It's also unknown how much better the subject might be if they pedaled properly. The wattage they are producing is that of a fairly strong pro at LT. If they are not a such a pro, then they are producing wattage far exceeding their normal output, and it would be normal for their pedaling style to deteriorate. Mine probably would too, though I'm fairly good at 200 watts.
I highly doubt your using your hams as much as you think. My experience with doing one legged drills is that it targets your upper hip flexors just as much if not more than your hamstrings. I find my hamstring being used much more at the bottom of the pedal stroke or the 'mud scraping' phase (which makes sense if you think about the dynamics).
If your rear wheel is coming off the ground you have very poor technique. I have heard that the main issue is not pulling up but rather you pushing down through the bottom of the stroke raising your hips and unweighting the wheel on the upstroke, but I am no expert. There have been a few posts in the past on this issue.