When Lance Armstrong surged ahead to drop Jan Ullrich on the final climb up the Alpe d'Huez in 2001, it wasn't his highly-publicized cadence that gave him his herculean burst of speed. Well, not really anyway. To beat Ullrich up the hill, Lance just had to push more power relative to weight into his pedals than Ullrich did. To simplify the math, assume that Armstrong and Ullrich were the same weight and each was pushing 400 watts on that final climb. A watt is equal to one joule of energy per second, so with Ullrich's deliberate, 80 revolutions per minute (rpm) cadence, Ullrich would have to push 150 joules with each pedal stroke. Armstrong, on the other hand, would only need to push about 120 joules to go the same speed at his 100 rpm cadence.
Here's the math:
400 watts = (400 joules per second) x (60 seconds per minute) = 24,000 joules per minute for each rider.
(24,000 joules) ÷ (80 rpm [Ullrich]) ÷ (2 legs) = 150 joules per pedal stroke
(24,000 joules) ÷ (100 rpm [Armstrong]) ÷ (2 legs) = 120 joules per pedal stroke
Armstrong's efficient pedaling technique allowed him to tax his aerobic system rather than his fast-twitch muscle fibers in the miles leading up to the Alpe, so his muscles were fresher for the final push to the end when he would use maximum strength and cadence to shake Ullrich off a few minutes from the mountain-top finish. So how can recreational riders learn to pedal like Lance?
The Mechanics of Pedaling
Pedal rotation can be thought of as a clock with the greatest amount of power generated between 2 o'clock and 5 o'clock. Human legs are made to generate power by pushing down as in running and jumping, but with some work, dedicated pedalers can learn to generate power through the rest of the pedal stroke as well. Countless scientists hired by the cycling industry have spent endless hours studying the "dead spots," or spots where no power is generated at the top and bottom of the pedal stroke (12 o'clock and 6 o'clock). Even elite bike racers who do not work on their pedaling mechanics generate almost no power in the "dead spots," giving a tremendous advantage to those savvy enough to work on their pedal stroke.
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.
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