Placebo effect of facilitatory Kinesio tape on muscle activity and muscle strength

Abstract

Purpose: Kinesio tape (KT) is claimed to be able to facilitate muscle activation and promote muscle strength. Previous studies have proposed that placebo effect could be a major attributing factor. This study sought to compare the effects of facilitatory KT on muscle activity and performance between regular KT-users and non-users.

Methods: Sixty participants, including 27 regular KT-users and 33 non-users, performed maximal grip assessment with and without facilitatory KT, which was applied to their wrist extensor muscles of the dominant forearm from the direction of origin to insertion at 75% of its maximal tension. Within-subject comparisons of normalized root mean square of the wrist extensors electromyographic activity, maximal grip strength, and perceived performance were conducted.

Results: KT-users showed an increase in grip strength with application of facilitatory KT, when compared to tapeless condition (p = 0.030, Cohen's d = 0.16). Non-users demonstrated similar grip strength with and with KT application (p = 0.232). No significant differences were found in the muscle activity (p > 0.198) and perceived performance (p > 0.400) in both groups.

Conclusions: Facilitatory KT promotes maximal grip strength only among regular KT users, but its effect is trivial. Interestingly, such effect is not related to any electrophysiological change in the KT applying muscle, which may indicate an indirect working mechanism leading to the increased grip strength.

Keywords: EMG; Placebo; facilitation; muscle strength; therapeutic taping.