Q: A student of mine recently got a bad sprained ankle, and it's been weak ever since she returned to class. Are there any exercises you suggest to strengthen it?
A: Your student needs to begin her recovery process by retraining her nervous system to find center at the ankle joint. The human body immediately compensates after an injury, which, in turn, inhibits balance. Therefore, balance is essential to the rehab process. If we don't take the time to retrain the musculature around the joint through balancing, the body will continue to act in a compensatory pattern.
First, have her start by balancing on one foot while making sure she's not sinking into her hip. Try this first with her standing leg in parallel, and then later have her move into a slightly turned-out position. Direct her to toss a ball between her hands while balancing for one to three minutes. (When I was training gymnasts, I would make them do this on the balance beam, so our dancers have it easy!)
When she gets good at balancing for three minutes on one leg, challenge her nervous system by having her stand on a moveable surface, such as a sofa cushion or her bed.
The leg muscles that fatigue first indicate weakness and/or tightness. By continuing to do the balancing exercises, you will strengthen and retrain the muscles that were injured. This exercise is just as important as strengthening through relevés or working with a TheraBand.