Well, I have to say I have been riding a lot so far this year. But I've only done flats, and today I did a 13 mile hill route. Used to do it all the time. It was my easy, "I only have a little while to ride" route. But it knocked me silly. Had to stop many times to catch my breath, drink something, and eat something. Guess this girl needs to forget the flats for awhile... The weather was nice though! The drivers were friendly, and there wasn't a dog to be seen!