If your sport is jumping or if you participate in another sport that requires any vertical jump skills, you can get a leg up by actively training yourself to increase vertical height in your jumps. Some great exercises for this are the dead lift, step ups, squats and lunges. When you squat, your goal should be to squat two times your body weight. One and a half times your body weight would be an acceptable minimum goal, but once you have reached it aim higher. Also practice various kinds of jumping. Do some lower impact jumps to protect your joints.