KT tape is very, very helpful in giving my daughter arch support while barefoot in the gym. She has to spray her ankles and bottom of her feet with alcohol and then dry first, so it will stick. (sweaty feet are tricky that way) She uses 2 strips per foot and ankle, per practice. (she takes it off after practice)
We use the "original" version of the KT tape- it's less stretchy, and gives better support. Just the bit of stretchiness seems to work for my daughter in her particular case.
She has very flat (pronated) feet, and wears ankle braces to minimize this pronation while barefoot, and wears the KT tape underneath the braces. The KT tape virtually prevents her plantar fascitis from flaring up. (as we have tested this several times)
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