One of the best exercises to improve the height of your straddle jump is the Straddle Leg Lift. This is an easy exercise that you can do at home while sitting in front of your television. Just make sure you have a large enough area to sit down in a straddle position on the floor. Start with either leg a just start lifting it off the ground, using controlled movements. You don't want to just start slamming your leg up and down. Repeat 15 lifts on both legs, 2 times each or just add this exercise in whenever you have some extra time.