We've been talking a lot lately about proper petal mechanics and I wanted to get some facts out to those of you in Spin class. The myth has been floating around class for awhile that if you're wearint clip-ins that you should be "pulling" the petals up. Just in case you don't believe me that this isn't the proper form, here's some info from an article I picked up.
I've bolded a few of the lines
Put Pedaling Technique into Practice
An efficient cyclist's legs aren't pistons mashing up and down on the pedals. Rather than relying on momentum to swing the pedals through "dead spots," instead imagine your feet drawing ovals: pushing forward over the top of the pedal stroke and pulling back through the bottom. At the top of each pedal stroke, imagine that you are throwing your knee over the handlebars. At the bottom of the pedal stroke, imagine scraping dog doo off the ball of your foot.
While some well-intentioned but misleading articles may advise novice cyclists to pull up on the pedals in the recovery phase of your pedal stroke (between 7 o'clock and 11 o'clock), in fact elite cyclists draw very little power from pulling up. Only sprinters and racing hill climbers derive power from pulling up on the pedals when they are pedaling at maximal effort. If a rider pulls up too hard on her pedals during a long ride, then she will needlessly fatigue her hamstrings. Instead, focus on pulling your leg up just enough that the opposite leg doesn't have to compensate for the dead weight. Once pushing through the whole pedal stroke is mastered, riding at a higher cadence without bouncing is easier.