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Old 05-04-06, 02:02 PM
  #16  
San Rensho 
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Originally Posted by DannoXYZ
Good examples of sprinting form. Additionally, being out of the saddle for sprinting is NOT the same form as being out of the saddle for climbing. A lot of people stand straight up and block a lot of wind. You want to be bent over with your nose over the bars and almost touching. Then it's the pulling motion of your arms that keeps your upper body from being pushed up by the leg forces.

Also gearing is very important, about 50% of the equation or even 60%. The gears lets you maximize whatever strength you have in the legs. Even if you're build like a linebacker and can leg-press 1000lbs, you'll still get beat by a scrawny 120lb climber if you pick the wrong gears. I typicaly go through 2-3 gears in a sprint. That's to get maximum acceleration speed in the beginning, then I shift up at around 130-135rpms or so and hold the last gear in the saddle spinning as fast as I can with my nose behind the bars.

What happens is you only have 25-30 seconds at 100% effort. If you're in too big a gear, it may take you 20 seconds to go from 20-30mph and you only have little energy after that. In a lower gear, you can go from 20-30mph in only 15 seconds, you're pulling away from the guy in the taller gear. AND... you have an extra 5 seconds left before you completely run out of steam, so you'll hit a higher top-speed.

Another thing is to not go all out from the beginning, but ramp up the effort to save most of your strength for the higher speeds. So from 20-25mph, I'll push 97%, then 98% from 25-30mph, then 100% from 30mph onwards. This also simulates real race conditions as well where you're drafting a lead-out for most of the sprint.

Last thing is the neural-muscular connections and timing. There's a pattern of muscle contractions around the pedal-revolution and timing them is critical. Your brain needs the training of firing these muscles off in just the right sequence and if you don't have the practice, it doesn't work well. That's where spin-up exercises really help. Easiest is when cresting a hill, stay in the same gear and spin up as fast as you can and let gravity increase your speed, you just try to keep the legs moving faster and faster. Aim for 160-180rpms on the downhills over and over again. This programs the brain to fire off the nerves at high-speed in the right sequence. Stationary gym bikes are good for this too as they're stable and lets you really crank up the RPMs, although they only go up to 199rpms...
Good advice. Spinning is definitely the way to sprint. I used to do a drill where a small group of us would do sprints in a very small gear, say a 42X16. It wasn't necessarily the strongest rider that won, but the one with the smoothest, best spin. To be able to spin big gears, you have to spin small ones first.
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