Effects of protective knee bracing on speed and agility.

We evaluated the effects of prophylactic knee braces on athlete speed and agility, as well as brace tendency to migrate. Thirty college football players in full gear ran a 40-yard dash and a four-cone agility drill wearing braces on both knees or no brace (control). Braces included the DonJoy Legend, Breg Tradition, OMNI-AKS 101W, McDavid Knee Guard, and models 1 and 2 of the Air Armor Knee and Thigh Protection System. Brace migration and subjective measures were recorded after each trial. In the 40-yard dash, times using Air Armor 1 and OMNI did not differ significantly from control. Times with other braces were significantly slower. In the four-cone drill, only the Breg times were significantly slower than control. The Air Armor 1 and McDavid braces showed significantly less superior/inferior migration in the 40-yard dash than other braces. In the four-cone drill, the Air Armor 1 and 2 showed significantly less superior/inferior migration than other braces. These findings indicate that selected knee braces do not significantly reduce speed or agility. Braces showed a variable tendency to migrate, which could affect their protective function and athlete performance. This information will help athletes and coaches decide about knee-brace use during sports; studies are needed regarding whether braces protect against knee injury. This study does not constitute an endorsement of knee-brace use or efficacy.