Athletes with various types of knee problems often wear knee braces for support, in the hope of preventing additional knee injury. Do these braces have any effect on performance? To find out, researchers at Arizona State University asked 30 college football players in full gear to run 40-yard dashes and four-cone agility drills while wearing either braces on both knees or no braces at all (the control group). The braces used in the study 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.

In the 40-yard dash, the only players running faster times than the no-brace controls were those using the Air Armor 1 and OMNI. The braces did better as a group, however, during the four-cone agility drill, when all of the braced players except those using the Breg model were as good as the controls.

One problem with braces is that they tend to slip off the knee during running. During the 40-yard dashes, the Air Armor 1 and McDavid braces showed significantly less superior/inferior slippage than the other models. In the four-cone test, the Air Armor 1 and 2 were best for non-slippage.

This study showed that some knee braces can indeed slow athletes down - and that the Air Armor 1 brace was a top performer. The Air Armor 1 was no slower than control during either the 40-yard dash or cone drill, and it slipped very little during the two tests.

The American Journal of Sports Medicine, vol 28(4), pp 453-459, 2000