Stronger skiers will always be able to rip the bumps longer, faster and better than a weak skier. Being strong also give you the ability to correct errors such as pulling your self out of the backseat. One easy way is to jump over a stool from side to side, to build leg strength and also simulating mogul skiing. Remember that it’s important to strengthen not just your legs, but strengthening your core is also extremely important. Here’s two videos with some great ideas: