{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,11,4]],"date-time":"2026-11-04T07:50:26Z","timestamp":1793778626690,"version":"4.6.1"},"reference-count":26,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2026,1,18]],"date-time":"2026-01-18T00:00:00Z","timestamp":1768694400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Objective: to clarify differences in the intermuscular coherence of core muscles during side kicks among male Sanda athletes at varying skill levels, particularly in critical frequency bands; to reveal the association between neuromuscular coordination mechanisms and technical proficiency; and to provide methodological references for quantitative analysis of combat sports techniques. Methods: Thirty-six male Sanda athletes were divided into professional (n = 18) and amateur (n = 18) groups based on athletic ranking and training duration. Surface electromyographic (EMG) signals from 15 core muscles and kinematic data were synchronously recorded using a wireless EMG system and a high-speed camera. Signal processing extracted root mean square amplitude (RMS) and integral EMG (iEMG). Muscle coordination was quantified via time-frequency coherence analysis across alpha (8\u201315 Hz), beta (15\u201330 Hz), and gamma (30\u201350 Hz) bands. Results: The professional group exhibited significantly higher RMS and iEMG values in most core muscles (e.g., rectus femoris RMS: 0.298 \u00b1 0.072 vs. 0.214 \u00b1 0.077 mV, p &lt; 0.001). Regarding intermuscular coherence, the professional group demonstrated significantly superior coherence in the \u03b1, \u03b2, and \u03b3 bands for key muscle pairs, including upper limb\u2013swing leg, support leg\u2013swing leg, and upper limb\u2013support leg. Notable differences were observed in pairs such as external oblique\u2013rectus femoris (alpha band: 0.039 \u00b1 0.012 vs. 0.032 \u00b1 0.011, p &lt; 0.01) and right rectus femoris\u2013biceps femoris (beta band: 0.033 \u00b1 0.010 vs. 0.023 \u00b1 0.007, p &lt; 0.01). Conclusions: The fundamental difference in side kick technique among Sanda athletes lies in neuromuscular control strategies and muscle coordination efficiency. Sensor-based intermuscular coherence analysis provides an objective quantitative indicator for distinguishing technical proficiency, offering a scientific basis for optimizing training and extending the methodological framework for technique assessment in combat sports.<\/jats:p>","DOI":"10.3390\/s26020646","type":"journal-article","created":{"date-parts":[[2026,1,19]],"date-time":"2026-01-19T14:58:54Z","timestamp":1768834734000},"page":"646","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Differences in Muscle Inter-Phasic Coherence During Side Kick Techniques Among Male Sanda Athletes of Different Skill Levels Based on Sensor Analysis: A Cross-Sectional Study"],"prefix":"10.3390","volume":"26","author":[{"given":"Liang","family":"Li","sequence":"first","affiliation":[{"name":"China Wushu School, Beijing Sport University, Beijing 100084, China"},{"name":"School of General Education, Beijing Normal-Hong Kong Baptist University, Zhuhai 519017, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Tianxing","family":"Liu","sequence":"additional","affiliation":[{"name":"China Wushu School, Beijing Sport University, Beijing 100084, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Guixian","family":"Wang","sequence":"additional","affiliation":[{"name":"China Wushu School, Beijing Sport University, Beijing 100084, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,1,18]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1938","DOI":"10.1177\/0363546520964454","article-title":"Blood Flow Restriction Training for Athletes: A Systematic Review","volume":"49","author":"Wortman","year":"2021","journal-title":"Am. 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