I agree with Missydog,

I am a cyclist, but of the mountain bike sort. I don't understand all that good stuff these trainers do, but I can tell you that you will get used to it. Your body will respond and take care of the problem, just continue to work at it.

Since starting Atkins, I can do about 18 miles off-road without stopping for a break. I do drink lots (usually 2-3 litres) from a hydration pack, and I would suggest you do the same.

On a road bike, you should be making quick distance gains. I have only tried road biking once with a buddy, but I believe we did about 20 miles. I like off-roading with a little more action.

Good luck,
wsgts