More shifting/hill questions

[Kiwi Stoker]

I have to agree with Darcy re changing from big to small chainring at the front.
Changing under load will most likely cause your chain to fall off. It's better too change the front one earlier and shift your rear gears harder to compensate. This is especially if a steep hill is coming up.

Regarding cadence, I am a slow one, only averaging around 70. Both DH and I have big leg muscles and whenever I spin very fast I start to bounce in the saddle and feel like I am going to fall off.

I think everyone is different and it depends on how you are built. If you are tall and lean, your muscles might be better going at a high cadence, but if you are built for strength, then a slower cadence is right for you. It does take a while to figure out what works for you especially as you lose weight and gain fitness.

[OakLeaf]

whenever I spin very fast I start to bounce in the saddle and feel like I am going to fall off.

/partial hijack

That's technique, not nature. If you're pedaling in squares at 120 rpm, you're still pedaling in squares at 70 rpm, it's just not as noticeable because the bouncing isn't as frequent and you can correct it with your other side. Even if your preferred natural cadence is low, high cadence drills (and one legged drills) are super valuable for smoothing out your pedal stroke and making you more efficient at any cadence.

As I understand it, the only way to know your true natural cadence is through time trialing. Now, this assumes an efficient pedal stroke, so you've got to work on pedaling in circles first. But once you have a good pedal stroke...

Mark yourself out a five-mile course and give it everything you've got. Record your time, speed, heart rate and cadence, but DON'T watch them during your TT. Just ride at the highest perceived exertion that you can maintain for the whole five miles.

Then give yourself a few days' recovery and do the same course, but this time watch your cadence monitor and make yourself spin 5 rpm higher than what you did the first time. Still give it everything you've got. Compare your speed and heart rate to your first trial. Faster? Slower? Higher or lower HR?

If you're less efficient on the second trial, try a third trial but this time pedal 5 rpm slower than you did the first time. If you're more efficient on the second trial, do your third trial 5 rpm faster than you did the second time . Repeat the process until you've found your most efficient cadence.

Size of muscles doesn't have anything to do with it - it's the composition of your muscle fibers. (Actually, I really have no idea about this latter, but I guess I had the impression that muscle hypertrophy was mainly fast-twitch fibers, since you develop large muscles by working under resistance and developing power, whereas long endurance and slow-twitch fiber work tends to develop long, lean muscles).


/hijack


Anyway, to the OP, I think you've gotten some good advice, and you could also take a look at some of the threads that Catrin has started on the same topic. It's really a matter of experience. You learn your leg strength and when the amount of pressure you're putting on the pedals is too high or too low for you; you learn your ideal cadence; you learn to read hills and anticipate the shifts. You'll get there!