A dynamic program of ankle motion, strengthening, and improving proprioception (joint position sense) is always recommended first. In any barefoot sport that relies heavily on the foot and ankle, function, motion, strength, and stability are essential.
In trampoline and other gymnastic events, the ankle must respond to even the tiniest wobble or landing that isn't right on. Previous ankle injuries, weak ankles, or less than normal joint motion can increase your risk of injury. Improving proprioception has been shown beneficial as well.
Once you have these key ingredients as part of your daily training program, you may not need any further support. But if you do, then experts suggest you may want to consider using a soft lace-up or velcro strap brace.
The semi-rigid aircast works well once you've sprained your ankle because it doesn't allow you to plantar flex or point your toes. Any loss of plantar flexion when there's no injury present will compromise your work on the trampoline. Should you find yourself with an ankle sprain, the Aircast is a good choice during the acute or early phase of healing.