Low ankle sprains are common in competitive sports, but they seem to occur most frequently in indoor volleyball. Injuries at the net are so frequent that Monash University’s Accident Research Centre performed a study on the topic, called Spiking Injuries Out of Volleyball: A Review of Injury Countermeasures.
Most volleyball injuries occur at the net, caused by the quick lateral and vertical movements needed during game play. Because there are usually three tall people on each side of the net, all within inches of the centerline, things can get dangerously tricky. That’s why coaches stress proper footwork! But, as we all know and have experienced, proper footwork on our side of the net doesn’t always mean proper footwork on the other side. (Just in case, see STACK’s article on a 3-Part Strategy to Prevent Ankle Injuries.)
An ankle injury is not the end of the world or the end of your sports career! I’ve had three major ankle injuries, and after each of them, I rehabbed and returned to the court a better and more knowledgeable player than I was before. Rise above your injuries, learn from them, strengthen your muscles, and you will achieve success in your sport.
Although most ankle injury physical therapy techniques are similar, here are the ones I have personally sworn by throughout my athletic career.

Dorsiflexions, Plantar Flexions, Inversions and Eversions

These are technical terms for the various directions to stretch and strengthen your ankle. The trick with each of them is to slowly move your ankle into position until you feel discomfort or can no longer turn your ankle and hold. Complete 10 reps of each move twice a day.

Dorsiflexion

Sit with your leg on a chair supporting a locked and straightened knee, with your foot dangling in the air. Using only your ankle, begin by pointing your foot towards your nose. Hold for 15 seconds and return.

Plantar Flexion

Next, while keeping your leg in the same position, point your foot forward and hold again for 15 seconds and return.

Inversion

While keeping your toes pointed up, turn your foot inward. Try to aim your sole at your other leg. Hold for 15 seconds and return.

Eversion

Finally, again keeping your toes pointed up, turn your foot outward, away from your other leg, and hold for 15 seconds.
As you begin to gain more movement from these exercises, you can begin my next favorite PT moves:

The Alphabet

Again, start by placing your leg on a chair with your foot dangling in the air. Then write the alphabet by working your ankle muscles and using your big toe as a “pencil.”
As you gain strength and another week passes, complete the same flexions but add a resistance band. For the Plantar Flexions, hold the end of the resistance band in your hands at your abdomen, allowing your ankle to pull on the band while flexing. For the Dorsiflexion, Inversion and Eversion, I like to wrap the band around a table leg, or have friend hold it while I flex.
Finally, the exercise to end with and perform often before returning to practice is the Single Leg Calf Raise. Begin standing next to a wall for balance. On the injured ankle, slowly rise, lifting your heel off the ground while keeping your toes firmly planted. Lift as high as you can, then return. Do 10 reps at least twice a day, even after you feel you are rehabbed and ready to play.