When weakness of the quadriceps femoris was induced via prolonged vibration stimulation, the use of kinesiology tape around the knee joint appeared to significantly reduce the weakness, according to recent research.
The study, “Tactile stimulation with Kinesiology tape alleviates muscle weakness attributable to attenuation of Ia afferents,” involved 10 healthy males with an average age of about 22 years.
The subjects all engaged in daily sports on a regular basis. These sports included long jump, triple jump, short sprint and long sprint. None of the participants had experienced any injury to the knee joint.
However, this study was designed to investigate the efficacy of tactile stimulation—in the form of kinesiology tape—on muscle weakness that is neurophysiologically similar to the muscle weakness seen among people who have suffered a knee injury.
“Substantial weakness of quadriceps resulting from neurophysiological abnormalities is typically observed following knee injury or associated pathology and remains long after other symptoms abate,” states the study’s author.
According to the researcher, these “neurophysiological abnormalities” may be caused by damage to structures around the knee joint, such as the ligaments, capsules, skin and gamma motor neurons.
“If these structures are damaged, their mechanoreceptors would also be histologically affected, and feedback would be hindered,” states the study’s author. “Normal afferent feedback from mechanoreceptors would not be sent to gamma motor neurons, which are important for Ia afferent modulation.”
The researcher hypothesizes that “hindered recruitment of these motor units is a possible mechanism for persistent [quadriceps femoris] weakness.” In order to create a neurophysiologically similar weakness among the study’s healthy subjects, the researchers used prolonged vibration stimulation.
The two outcome measures for this study were maximal voluntary contraction (MVC) during knee extension and electromyography (EMG) signals from the muscles, which were recorded during the MVC measurements.
All subjects in the study were evaluated in two different sessions, one with the use of kinesiology tape and one without the use of kinesiology tape, each conducted more than a week apart. Measures of MVC and EMG were taken immediately before and after the prolonged vibration stimulation.
A machine called the Hit Masser was used to apply the vibration to the mid-portion of the infrapatellar tendon for 20 minutes. Subjects were seated with their legs hanging down, and they were instructed to relax their thighs as much as possible during the vibration. According to the study’s author, the vibration was used “to induce attenuation of Ia through the tonic vibration reflex of the quadriceps muscle.”
During the taping session, kinesiology tape was used to cover the anterior side of each subject’s knee joint, from the tibial tuberosity to 5 centimeters above the superior edge of the patella. This occurred immediately after the vibration stimulation, just before MVC and EMG measurements were taken.
The researcher reports that no tension was used during the application of the kinesiology tape, and that this tape is designed to give cutaneous stimulation and still allow for freedom of movement.
Analysis of the data showed that both MVC and EMG scores following prolonged vibration stimulation were significantly higher when the kinesiology tape was used, as compared to when no tape was used.
“Our results suggest that tactile stimulation in the form of kinesiology tape inhibits the decline of both strength and electromyography,” states the study’s author. “Alpha motor neuron activity attenuated by prolonged vibration would thus be partially rescued by tactile stimulation. These results indirectly suggest that stimulation of the skin around the knee could counter quadriceps femoris weakness due to attenuated Ia activity.”
Author: Yu Konishi.
Sources: Department of Physical Education, National Defense Academy, Japan. Originally published in 2012 in the Journal of Science in Medicine and Sport.