Great article and video from NYTimes;
A growing body of research suggests that many of those second (and often third and fourth) sprains could be avoided with an easy course of treatment. Stand on one leg. Try not to wobble. Hold for a minute. Repeat. This is the essence of balance training, a supremely low-tech but increasingly well-documented approach to dealing with unstable ankles. A number of studies published since last year have shown that the treatment, simple as it is, can be quite beneficial. – from NYTimes