Does elastic taping on soles improve flexibility? A randomized controlled trial with equivalence test design.

Abstract

Elastic taping that applies shear force affects joint movement. However, it remains uncertain whether elastic taping or stretching is more effective in improving flexibility. We investigated whether elastic taping for flexibility improvement is comparable to traditional stretching. In this randomized controlled trial, 64 university students were randomly allocated to two groups: elastic taping on the sole or 30 s of static stretching. The primary outcome measures were the straight leg raising angle, tested with an equivalence margin (± 9.61∘ on changes), and the fingertip-to-floor distance. Secondary outcomes were the hip flexor and knee extensor strength, two-step distance, adverse events, and pain intensity during the intervention, which were compared using conventional statistical methods. The mean differences in straight leg raising between the two groups after the interventions were not greater than the equivalence margin (mean [95% CI]: 1.4 [-6.9, 9.5]; equivalence margin, -9.61∘ to 9.61∘). There were no consistent differences between groups in terms of secondary outcomes except for pain intensity during the intervention (p> 0.05). Elastic taping did not induce pain. Elastic taping augments the flexibility-improving effect comparable to static stretching, based on an equivalence margin. Elastic taping of the sole appears to be an alternative method of improving flexibility.