Iranian Rehabilitation Journal

en Comparison of Push-Off Lower-Limb Muscle EMG Mean Frequency Before and After Running-Induced Fatigue in Runners with Pronated Feet Using Carbon-Plated and Highly Cushioned Non-Plated Shoes توانبخشی Rehabilitation پژوهشي Original Research Articles Abstract Objective: The aim of this study was to compare push-off lower-limb muscle EMG mean frequency between recreational male runners with pronated feet using carbon-plated and highly cushioned non-plated footwear, with particular attention to muscles involved in late-stance stabilization and propulsion. The comparison was intended to examine neuromuscular responses to the overall biomechanical characteristics of the two footwear constructions rather than to isolate the effect of the carbon plate alone. Methods: Thirty recreational male runners with pronated feet were randomly assigned to a carbon-plated ATF group (Nike ZoomX Vaporfly Next% 2; n = 15) or a non-plated cushioned footwear group (Nike Invincible Run 3; n = 15). Surface electromyographic activity of the vastus medialis, vastus lateralis, rectus femoris, biceps femoris, semitendinosus, medial gastrocnemius, tibialis anterior, and gluteus medius was recorded during overground running at 4.5 m/s before and immediately after a treadmill-based fatigue protocol performed at 4.0 m/s. Push-off EMG mean frequency (MNF) was calculated for all analyzed muscles. A two-way mixed repeated-measures analysis of variance was used to examine footwear-group, fatigue, and footwear-group × fatigue interaction effects. Results: Baseline demographic characteristics and Foot Posture Index scores did not differ between groups (p > 0.05). Compared with the non-plated cushioned footwear group, the carbon-plated footwear group demonstrated higher overall push-off EMG mean frequency (MNF) values in the vastus medialis (p<0.001, η²p = 0.291), vastus lateralis (p<0.001, η²p = 0.220), and biceps femoris (p<0.001, η²p = 0.251). Across footwear groups, post-fatigue testing was associated with higher semitendinosus MNF (p<0.001, η²p = 0.330) and higher biceps femoris MNF (p = 0.001, η²p = 0.159). A significant footwear-group × fatigue interaction was observed only for the medial gastrocnemius (p = 0.001, η²p = 0.163), indicating that the pattern of pre- to post-fatigue change differed between footwear groups, with MNF increasing in the non-plated footwear group and decreasing in the carbon-plated footwear group Conclusion:  Carbon-plated footwear was associated with higher push-off EMG mean frequency in the vastus medialis, vastus lateralis, and biceps femoris. Fatigue increased mean frequency in the semitendinosus and biceps femoris, while the medial gastrocnemius showed different fatigue-related responses between footwear conditions.   Advanced Technology Footwear, Carbon-Plated Shoes, Electromyography, Fatigue 0 0 http://irj.uswr.ac.ir/browse.php?a_code=A-10-2490-2&slc_lang=en&sid=1 Mohsen Barghamadi barghamadi@uma.ac.ir 11111111111 0000-0002-1794-9410 Yes Department of Sport Biomechanics, Faculty of Educational Sciences and Psychology, University of Mohaghegh Ardabili, Ardabil, Iran. Ladan Barzegarfar Ladanibrzf@gmail.com 11111111111 0009-0002-0555-5622 No Department of Sport Biomechanics, Faculty of Educational Sciences and Psychology, University of Mohaghegh Ardabili, Ardabil, Iran. Ebrahim Piri ebrahimm.piri@gmail.com 1451157010 0000-0001-9188-9746 No Department of Sports Biomechanics, Faculty of Educational Sciences and Psychology, University of Mohaghegh Ardabili, Ardabil, Iran.