Neoprene knee sleeves are used extensively in Olympic and Powerlifting. We explore one of the possible benefits – proprioception. Proprioception is the information we receive from our muscles informing us of joint position.
Lephart (1997) suggests the mechanism for increased proprioception is an increase in augment afferent input resulting from increased cutaneous stimulation. Perlau (1995) added that free nerve endings, hair end organs and Merkel’s discs also increase joint awareness.
Studies into EMG and muscle activation patterns with a knee brace reveal no changes in muscle activation. This indicates that it is primarily the cutaneous receptors increasing output frequency and amplitude, as the muscle activity does not change.
An implication of this improvement is the concept of elite athlete performance versus unskilled athlete performance. Cawley (1991) found that a knee brace has the same injury preventative effect as proficiency in a motor skill. Elite athletes respond to relevant proprioceptive feedback, increasing the efficiency of proprioception, while the knee bandage increases the magnitude of proprioception with the same resulting effect.
This improvement may be explained by drawing a parallel with a study completed by Ferrel (1989). It was found that an excessive amount of fluid in the knee joint leads to an improved knee joint position sense. It was proposed that this is due to an increase in knee joint capsular tension, thus increasing joint capsule mechanoreceptors. I suggest a similar mechanism provides a reason for the increase in proprioception with the use of a knee sleeve, with an increase in pressure and tension increasing the firing rate and amplitude of cutaneous mechanoreceptors.
Although it appears from prior research, our results and an understanding of cutaneous and joint mechanoreceptors that the use of a knee sleeve does have a beneficial effect on joint position sense, there are other variables which may explain the improvement in this branch of proprioception.
The improvement may not be due to a beneficial effect of the sleeve on the afferent output from cutaneous mechanoreceptors, but rather due to an increased awareness of movement. Horch et al (1975) found that although the fingers have a high level of sensory innervation, cutaneous mechanisms are unable to signal the static position of a joint, though they do contribute to movement sense. The increased effects caused by a brace may therefore result from the increased sensation of movement of skin and underlying tissue during joint movement. The tightening of the brace causes the skin to move over muscle and underlying subcutaneous tissue, allowing better awareness of distance moved. This suggests an improvement in kinesthesia, which the subjects use to identify distance traveled in the range of motion and thus arrive at the target joint angle.
The findings of Feldman et al (1982) support this hypothesis. It was found that muscle afferent signals deliver not relative, but absolute information. These signals turn out to be related to active muscle torque. This suggests that it is not the position sense in the muscles which identify proprioception but the movement. Feldman proposed that the same occurs in cutaneous mechanoreceptors.
The use of knee braces and sleeves in dynamic movements assists with knee stability. Research suggests knee joint proprioception is increased by the application of a knee sleeve, due to its effect on cutaneous mechanoreceptors.