I went for a fairly technical (by my standards) cross country ride last weekend, that was absolutely brutal. I had a lot of trouble keeping my pace on the climbs and the next day, my knees were extremely tender. They stayed that way most of the week. I'm trying to figure out why the ride was so hard on my knees was wondering, could I have had my seat too high on that ride? I tried a gentler ride this weekend with the seat a little lower. My knees were still a little tender, but none the worse for this ride.
I normally ride with my leg not quite straight at the bottom of the stroke, but I think I might have raised the seat a little too far after taking the bike out of the car. Was my leg straightening out messing with my knee? Did I lose some power in my stroke, as well? What can I do to strengthen my knees.