I am posting this here because I actually do have a tiny part of a soul hanging out somewhere in my body that occasionally tells me to help people out.
Skiing, by nature is incredibly abusive to your body, and being in shape really does help out in keeping you from getting injured, as well as it allows you to ski faster and harder all day.
One way to help you understand the impacts your body takes is to load up a barbell to about your weight and imagine dropping it from 10 ft. Many of us absorb drops from a lot higher then 10 feet. All that energy needs to be absorbed by your body.
Physical fitness involves more then just Aerobic and Anaerobic conditioning and physical strength. These are obviously important to your physical fitness, however, many people focus only on these three aspects, or possibly only one of them. The aspect most people overlook is your mobility, your range of motion.
I have been cursed with terrible range of motion my entire life. I would stretch religiously after working out, with limited results. Here is my 'born again' 'came to jesus' story.
About 6 months ago now I was introduced to a blog called MobilityWOD (mobilitywod.com). This is a blog dedicated to helping people increase their mobility and range of motion. The guy is a licensed PT, and is really dedicated to helping people increase their mobility.
If you want to avoid injuries this season, being mobile will probably go a long way to helping you out.
I strongly suggest you all go on over their and try it out. It is fucking awesome. Then you won't be like Grant who can barely lift his arms over his head.
Muscular fitness is also obviously important, get to a gym and lift some weights, you don't have to be pumping steroids, but lifting not only strengthens your muscles, but also your tendons and ligaments, it also helps keep you from looking like Scott~
mountainathleate.com has some great exercises for increasing your functional strength.