The Effects of High Heels on the Lower Extrenity Muscle Activotion in Women with and without Functional Ankle Instability While Ascending and Descending Stairs

Abstract

Background: Recent studies suggest that wearing high-heeled shoes (HH) increases the risk of musculoskeletal disorders. The aim of this study was to evaluate the EMG activity of the ankle muscles in women with and without functional ankle instability (FAI) during stair ascent and descent. Method & material: Thirty six subjects were studied in 4 groups as follows: group 1 consisted of 10 subjects with FAI and a limited experience of wearing HH (non-habitual FAI), group 2 consisted of 8 subjects with FAI and experience of wearing HH (habitual FAI), group 3 consisted of 10 subjects with healthy ankles and a limited experience of HH (non-habitual healthy), and group 4 consisted of 8 subjects with healthy ankles and experience of HH (habitual healthy). Electromyography (EMG) activity of the tibialis anterior (TA), peroneus longus (PL), and gastrocnemius medialis and lateralis (GM, GL) muscles were collected during stair ascent and descent with HH shoes and barefoot. Results: EMG activity of the PL, GM and GL muscles was significantly greater in the HH compared to the barefoot in FAI and healthy groups when descending and ascending the stairs. But the muscle activity TA showed different results. In the FAI group there was a significant increase in GL muscle activity during stair descending compared to healthy group. In FAI groups (non-habitual and habitual FAI), onset latency of the TA and GL muscles was longer in the HH compared to barefoot during stair asescent. In FAI groups (non-habitual and habitual FAI) and non-habitual healthy group, onset latency of the TA muscle was longer in the HH compared to barefoot during stair descent. Also, onset latency of the PL muscle during stair descend, was longer only in the non-habitual FAI subjects. Conclusion: The findings of this study suggest that HH shoes may put people with FAI and without experience of wearing HH at greater risk for developing ankle sprains.