In 1997, Bahr et al4 reported on a 3-year cohort study that evaluated a proprioceptive prevention program that included a didactic session on risk factors, a 2-hour training session on a balance board for players with previous ankle sprains, and technical training that emphasized safe takeoff and landing techniques.They found that the incidence of ankle sprains was reduced by 47% from the first to the third years, but they could not determine to what degree each of the program’s elements contributed to the overall results.