The Effect of Different Insole Surfaces on Running Biomechanics, Muscle Recruitment and Perceived Comfort

Abstract

0419 PURPOSE: The aim of this study was to investigate the effect of a rough or smooth surface of the same insole on running biomechanics, muscle recruitment and perceived comfort. METHODS: Twelve injury free runners ran 10 trials (5 at a self-selected speed and 5 at a controlled running speed) on either the rough (RI) or the smooth (SI) surface of the same insole in a randomised fashion. Kinetic, kinematic and temporal distance parameters were collected using the Oxford Metric Vicon System (Helen Hayes modified marker set). Electromyography (EMG) data were collected (Noraxon telemetry system – 1920 Hz), from the Lateral Gastrocnemius (LG), Rectus Femoris (RF), Biceps Femoris (BF), Tibialis Anterior (TA) and Vastus Lateralis (VL) muscles. EMG data (100ms prior to heelstrike) were filtered (10–200Hz) and the root mean square (RMS) amplitude over periods of 50ms was calculated. EMG was expressed as a percentage of the peak RMS EMG. Rating of perceived comfort (RPC) (VAS 0–10) was measured during a 400m run (85% of 5km time trial pace). RESULTS: There was a slower self-selected speed in the RI compared to the SI (RI: 2.99 ± 0.24 m/s, SI: 3.06 ± 0.24 m/s; p = 0.048). There were no differences in kinetic and kinematic variables between RI and SI conditions. Rectus Femoris recruitment was lower in the RI compared with the SI condition (RI: 1.47 ± 0.94 %, SI: 1.68 ± 1.13 %; p = 0.029). The RPC was similar in the RI (3.50 ± 2.50) and the SI (4.75 ± 2.18) (p = 0.056) conditions. CONCLUSION: Running on the rougher compared to the smooth surface of the same insole reduces self-selected running speed and recruitment of the Rectus Femoris muscle just prior to heel strike.