Influence of walking speed on electromyographic activity of the rectus abdominis and erector spinae during high-heeled walking

OBJECTIVE: This study aimed to determine the effect of walking speed on the electromyographic (EMG) activity of the rectus abdominis (RA) and erector spinae (ES) muscles during treadmill high-heeled walking at different shoe heel heights. METHODS: Twenty-five young healthy women volunteered to participate in this study. The subjects performed treadmill walking at speeds of 3 km/h and 6 km/h for 30 seconds under 3 high-heeled conditions: barefoot, 3-cm heels, and 7-cm heels. Surface electromyography (EMG) data were collected from standard sites on the RA and ES muscles during treadmill walking. RESULTS: For all heel heights, the EMG activity of the RA and ES muscles was significantly higher at the 6 km/h speed than at the 3 km/h speed (p < 0.05). Furthermore, EMG activity increased significantly with increasing shoe heel height, regardless of the walking speed (p < 0.05). CONCLUSION: These findings indicate that walking speed and shoe heel height may contribute to the increased activity of the trunk muscle during high-heeled walking. This study provides information for future studies performed with the aim of predicting possible changes in trunk muscle activity during high-heeled walking.