Develop your core
A strong back and abs will benefit just about every aspect of your life, including skiing. Better posture, less fatigue, less pain. Sit ups, crunches, plank poses, and superman extensions are all good core builders. Visit this Mayo Clinic site for a slide show of other good core exercise.
Strengthen your legs
Your legs do most of the work on the slopes, whether you ride or ski so give them a helping hand. Doing alternating lunges and squats can help strengthen quadriceps and hamstrings and ward off fizzling muscles. Be sure not to extend you knee beyond your toes during these exercises as that puts undue strain on knees. Here are some other ski-specific leg strengthening exercises you can try.
Build your endurance
Ensure you can enjoy those deep powder runs all day long by improving your cardiovascular health. That means doing things that make you sweat and breathe hard like running, cycling, and aerobics. Being physically fit not only enhances your day on the slopes, it helps prevent injuries that result from stressing unused, unpliable, weak muscles.
Dress for safety
You are going to fall down and even if you don’t crash into something, or someone, they may crash into you. So wear a helmet if you care about the health of your skull and its contents. Also wear multiple, warm layers and a waterproof outer layer. It will keep you from being cold and uncomfortable and could protect you from serious harm – frostbite or hypothermia – if you get stranded in the elements.