It doesn’t work, except as a placebo. It was invented by a chiropractor and based on pseudoscience. It does not support muscle or joints, as it’s just too flexible (even the “stiffer” versions). And it does not increase blood flow to the skin or any tissue.
The closest to any sort of efficacy that kt tape has is proprioceptive feedback–you feel the tape on your skin and change your behavior because of that reminder (usually that you’re injured). Wearing a soft elastic band accomplishes the same thing.
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