tramp for air practice if you want....lots of core workout,lower body (squats, etc) and some upper body to balance out ur body
"You put on your boots, click into your bindings, dust the snow off your skis, and head out for the chair, and it doesn't matter that you failed a test, didn't get the girl, or that your life is on a one way trip down the shitter, your world is right for the next couple of hours."
Hey, I`m part of the staff at the Dave Murray Whistler Summer Ski Camp, and i`m also a former camper. Some of the best ways to get some summer training in is going off of water ramps or even some summer ski camps! Our park is pretty sick, and no, you`re not just riding on rocks and mud. Its all snow, and we even make a trip to the water ramp at whistler after riding. I uploaded a video showing the water ramp, if you wanna check that out. If you wanna know more, go to www.skiandsnowboard.com
Water ramps are sick, not sure if there are any in Cali, Park City is probably best, but expensive if you don't have a hook up. There are also ramps in CO, but still a long way from Cali. Water ramps are pretty good training, but tricks don't transfer directly, but definitely helps confidence in the air, also will improve your technique a lot, especially if you have a coach helping you. Besides that I agree with mtn biking, but the best, and I can't believe no one mentioned this, is diving boards. You have to have a pretty dope setup to do a dub cork on a tramp, but it's nothing off a high dive. In any case, all of the legit skiers I ride with are in stupid good shape, that's probably your best bet.