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Background and Objective: Foot pronation could increase injury occurrence during running. This study was done to investigate the effect of shoes with spikes containing two different stiffness on frequency spectrum of muscles during running in patients with pronated feet.
Methods: This quasi-experimental study was done on15 pronated feet runners with mean age of 27.2±6.4 years. Running was done in two conditions including double density and usual spikes Track and field shoes with between rests of 5 minutes. A wireless 8 channels electromyography system (UK) with bipolar electrodes was used to record the electrical activity of the lower limb muscles. Electrodes were located on tibialis anterior, medial gastrocnemius, vastus medialis, retus femoris, vastus lateralis, biceps femoris, semitendinosus, and gluteus medius muscles in accordance with SENIAM European protocol.
Results: Frequency content of tibialis anterior and gluteus medius at loading phase were significantly greater during running with spikes double density Track and field shoes compared with usual spike shoes (P<0.05). The frequency content of muscles did not demonstrate any significant differences during running with spikes double density Track and field shoes compared with usual spike shoes at both mid-stance and push-off phases.
Conclusion: The double density spikes track and field shoes increased frequency content of tibialis anterior and gluteus medius muscles during loading phase that could be associated with shock absorption.