From Ergo Log
Knee wraps may help you to use heavier weights for squats and leg presses in the gym, but regular use might not be such a good idea. According to British sports scientists, knee wraps alter how you move during a squat in such a way that you're likely to cause more damage to your knee joints.
If you use knee wraps during strength training you can generate more power in your lower body. This has been officially known since 1990 [J Strength Cond Res 12: 30–35, 1990.], but long before this strength athletes had worked out that they could do heavier squats by using the things. It's probably the elasticity of the material that helps.
Little was known however about the effect of wearing knee wraps on how you carry out a squat. That's why sports scientists at the University of Chichester got 10 experienced male strength athletes to perform squats with [Wrapped] and without knee wraps [Unwrapped].
They discovered that there was a pronounced effect on how the movement is performed. During a squat the weight on your shoulder not only makes a vertical movement, but also a horizontal one. Wearing wraps reduced the horizontal movement considerably, the researchers observed.
As the weight was lowered [from a to b] the horizontal component of the movement decreased by 39 percent; as the weight was raised [from c to d] the horizontal movement decreased by a massive 99 percent.
As a result of the reduction in horizontal movement, the researchers suspect that friction in the knee joint increases, leading to more wear and tear.
This effect is reinforced because the knee wraps help the athletes to perform the movement faster: power increases.
"We therefore propose that knee wraps should not be worn during the strength and conditioning process and that if an athlete feels that additional support is needed for the knee, the integrity of the joint is thoroughly assessed and treated rather than relying on artificial aid that could exacerbate any underlying issues", the researchers write.
Charles Poliquin agrees with the British researchers' view of the matter. [charlespoliquin.com December 30, 2011] He also fears that strength athletes who always train their legs using knee wraps do not develop their hip muscles sufficiently.
J Strength Cond Res. 2012 Oct; 26(10): 2844-9.