Keep working your legs out, hop on the spin cycle on the off days, do squats, and keep the variety up when working out. Missing leg does fuck you over in the long run. Keeping the legs strong means stomping. Also stretch it out before you get on the hill, warm up for a bit and do some good stretches at the top of the lift after a few mellow turns to really get warmth going. Maybe a warm up lap or a hot lap is in order in the morning or right after lunch to get the blood flowing and the knees pumping. At the end of the day do the same thing to run the lactic acid out of your muscles and cool down before you have to sit in a car for a while or go party with your mates. Hope this helps man, I totally get ya, most of last season I had bad hip pains and just working out and building strength is what ya have to do to overcome it. A buddy of mine uses a supplemental brace when his knee is not feeling too strong some days to help him out. That seems to work and if it continues, you may want to go into a doctor to have them check it out.
