I recently moved to Colorado, and I've been riding a lot more frequently. I'm looking to get faster, but I think a big problem I'm having is my core strength. After an hour or so I start to slouch, and I start to slow down. I'm thinking of hiring a personal trainer to try and strengthen my core. Are there such things as cyclist strength trainers? Or should I just go to a normal personal trainer and explain my goals? Also, what sort of cost am I looking at to really get results over the winter?