I love standing on hills (well, what passes for hills in Florida, not mountains) because it feels good, changes the muscle groups around a bit, gives the undercarriage a break, and is like have a couple extra gears. But if the hill is long and steep, eventually it takes less energy to sit. I start sitting, move to standing when it feels right, (a bit before I run out of gears) then sit right when I feel lactic acid, if it's got much more to go. In a race, if I could, I would stand to climb as much as tolerable, because I go much faster.
Nanci
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"...I'm like the cycling version of the guy in Flowers for Algernon." Mike Magnuson