Again, bikeradar.com comes up with a gem of an article. If you're not making this website a part of your regular cycling-related web-surfing you are missing out on some seriously cool stuff.
Link to the article:
I also remember an article that appeared on one of the major cycling websites a couple of years ago, featuring Davis Phinney with some great climbing advice as well. I know it is hard to believe that you'd get good climbing advice from America's most successful sprinter (although Tyler Farrar is doing his best to try to unseat Davis), but after watching Thor Hushovd's solo breakaway and earlier; his lead-out man, Heinrich Haussler it becomes evident that; for those of us who are not natural-born climbers, the best ones to take advice from are the big "engines" who have to haul themselves over the huge climbs in the Alps and Pyrenees in order to have a shot at glory on the last day in Paris.
Anyway, to stop rambling and get back on topic: Phinney's advice was to approach a long sustained climb in a harder gear than you normally would, and start the climb in a standing position; climbing that way as long as you could sustain it without popping. Then shift to an easier gear and spin out the rest of the climb. The theory here being that the muscles you use in standing pedaling are somewhat different than those you use while sitting. Assuming that you've approached the climb seated, by standing for the opening segments of a long climb, you give your seated pedaling muscles a bit of a break while using the mechanical advantage of being able to use your body weight and upper body muscles to pedal. Then, when those muscles have recovered, you shift gears and sit to spin higher-cadence, lower strain gears up the remainder of the ascent.
To become proficient with this technique you certainly have to develop those standing muscles - they'll burn out pretty fast with your first few applications of this technique. But with some practice and development you'll find this is quite effective. Additionally, on the longest of climbs you'll find yourself being able to stand for longer periods and being able to go back to standing one or more times in order to rest the sitting muscles again. I began developing this in the rolling terrain of Tennessee and found it quite effective. Coming to the longer climbs of the Pacific Northwest, I found this method to be a great survival technique, especially on the ascents with punctuated changes in grade; like McNamee road from Highway 30 to Skyline here in Portland, where it fluctuates from 4-6% to near 20% and back to false flats several times in it's 4 mile length. Standing through the steeper sections can be an effective self-preservation move and a great way to put a gap on those in your group ride while battling for king-of-the-mountain points!
Thanks for reading and be sure to enjoy the last to days of the Tour!