Start with Isometric Exercises
Isometric exercises require you to push against a solid object. These types of exercises are the easiest to start with when strengthening your ankles, according to the American Orthopaedic Foot and Ankle Society, as the resistance helps strengthen the ankle and the surrounding muscles and joints. Stand next to your couch and place your ankle flush against the side or front. Put your ankle in a down and in position, pressing it up against the couch, and hold it for 10 seconds, recommends the CEMM Orthopedic Injury and Prevention website. Do the same thing again, but place your ankle in an up and out position. Place the top of your foot under the edge of the couch and push up, holding for 10 seconds.
Move on to Isotonic Exercises
Once you've mastered isometric exercises, move on to isotonic movements, the American Orthopaedic Foot and Ankle Society suggests. Resistance bands are a highly effective isotonic exercise tool that can help build ankle strength. Place a band around the bottom of one foot, holding one end of the band in each hand. Gently push your ankle down as far as you can, return to your starting position and then repeat 10 times. Tie the ends of the resistance band around a fixed object and place the top of your foot inside the band. Point your foot down and pull your ankle as far as you can. The American Council on Exercise suggests placing a resistance band around the ball of your foot so it's pulling the bottom of your foot away from your body. Point your toes and pull them toward your shin, return to the starting position and repeat.
Follow up with Proprioceptive Exercises
Once you've gained strength with isotonic movements, add proprioceptive exercises to your ankle-strengthening routine. Stand on one foot on a pillow, holding the position for 10 seconds and repeating 10 times, recommends the CEMM Orthopedic Injury and Prevention website. Stand on your weak leg and wrap a resistance band that's been tied to a stationary object around your stronger ankle. Pull on the resistance band or swing it behind your weaker leg as additional ways to build ankle strength.
Yoga can be an effective way to build flexibility in your ankles, which decreases the risk of injury, according to "Yoga Journal." Virisana, also called the Hero Pose, for example, can improve flexibility on the front of the ankle. Kneel down with your thighs perpendicular to the floor and your inner thighs touching. Move your feet slightly wider than your hips, exhale and sit back so your buttocks are on the floor between your calves. Hold the pose for 30 seconds to 1 minute. Tight calves increase the risk of ankle sprains, but strengthening them can help protect your ankle strength, according to Nicholas A. DiNubile and William Patrick, authors of "FrameWork: Your 7-Step Program for Healthy Muscles, Bones, and Joints."