I was just reading on this very topic today - a book called "Long Distance Cycling" by Edmund R. Burke and Ed Pavelka (sponsored by Bicycle Magazine). I know there are many different recommendations out there but I have listed some of the suggestions from the book on hill climbing. Hopefully it will help you.
1. Don't go anaerobic. Your best overall performance will come if you climb strongly but avoid the glycogen-gobbling consequences of switching to anaerobic metabolism. Is it better to stand or sit? It depends on the terrain and personal preference -what feels better to you. Most riders will find that sitting uses less energy because body weight is supported by the bike. For the majority of cyclists, going from saddle to standing causes an increase in heart rate in the range of three to five beats per minute.
2. The rule of thumb is to climb long, steady hills in the saddle to conserve energy. Even so, it's good to stand occasionally for a couple dozen pedal strokes. This increases comfort by changing by position and altering the muscles that are bearing the strain. Before rising, shift to the next higher gear (smaller cog) so you won't lose speed. Cadence tends to drop when you stand.
3. Don't lean too far forward when standing - this slows you by grinding the front tire into the pavement or causing the rear wheel to lose traction on a trail.
4. Use the right gear - the correct ratio when you're standing will make it feel like you're walking upstairs. The gear is too low if you're bouncing and feeling little pedal pressure causing you to power stroke too quickly. If you must work the bike from side to side with a grinding cadence, the gear is too high.
5. Go low - bail out gears can save the day on hilly rides
6. Keep your cadence up - on extended climbs, use a gear that you can pedal at about 70-80 rpm. This will be a relatively low gear helps control your heart rate for the entire hill.
7. Pedal in circles - Concentrate on pedaling across the stroke rather than simply up and down. The idea is to apply some power horizontally, especially through the bottom. This recruits more leg muscles and enhances momentum.
8. Shift just before you need to - anticipate shifts to lower gears such as when starting a climb. Don't shift too soon and waste precious momentum, but do shift before you're forced to apply heavy pressure to keep the crankset turning.
9. Start easy - to climb faster, begin in a lower gear than you need and shift up as you ascend. Coach Chris Carmichael says to imagine yourself as a carpet unrolling. It's the way pro road racers do it. The alternative - starting a long climb in the biggest gear you can handle - is likely to have you slogging away searching for a lower (and slower) gears well before the top. Be conservative early, and then you'll have the option of stepping up your pace.
10. Sit up - most roadies find they can't breathe as well if they grip the drops when climbing - the aerodynamic advantage of a low position isn't important at climbing speeds. Instead, grip the bar top or brake lever hoods to sit up and help your diaphragm expand.
11. Breathe deeply and rhythmically - to prevent shallow breathing concentrate on expelling air forcefully and completely, letting your lungs refill passively. Do this in sync with pedal strokes.
12. Slide on the saddle - on long, gradual climbs, move forward on the seat to emphasize the quads. After pedaling in that position for a while, slide back to relieve the quads and accentuate the glutes. These shifts help fend off muscle fatigue and extend your energy.
13. Relax your upper body - grip the bar lightly, bend elbows slightly, keep back flat and shoulders back so the chest is open for full, deep breathing.
14. Bob a bit - rocking your upper body helps establish a rhythm that aids climbing. Don't intentionally exaggerate this, but also don't try to prevent it - do what feels natural.
15. Train with weights - gain climbing power with squats or leg presses. For upper body - rowing exercises develop the strength to pull on the handlebars and balance the force exerted by the legs.
16. Finish every hill - it's natural to let up near the top of a climb when the crest comes into view. You ease pedal pressure to reduce the strain causing the pace to slow to a crawl. Instead, make time on every hill by not reducing your effort until gravity is pulling you the other way. You might even shift up and stand across the crest to stretch your legs and build extra momentum for the descent.
Sorry if it seems like a long post but I applied some of these techniques on my ride tonite and it really helped me tackly the hills.
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