Originally Posted by wristwister

Well then maybe I'm doing something wrong. I certainly don't ride "flat out". I ride at a comfortable, slightly agressive pace, always have. My legs STILL burn up those hills. I still arrive at my destination sweaty and spent. The difference is I get there quicker now, I'm riding up hills I once walked the bike up, and for some massochistic reason that leg burn and exhaustion feels good now!