{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,17]],"date-time":"2026-09-17T05:05:45Z","timestamp":1789621545063,"version":"build-2803163510"},"reference-count":47,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2026,9,17]],"date-time":"2026-09-17T00:00:00Z","timestamp":1789603200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Physiol."],"abstract":"<jats:sec>\n                    <jats:title>Objective<\/jats:title>\n                    <jats:p>This study aimed to examine differences in neuromuscular control strategies during the Tai Chi heel-kick movement between practitioners with different levels of motor experience by integrating estimated spinal segmental motor output, muscle synergy analysis, antagonist muscle co-contraction, and joint coordination assessment.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>Sixteen male Tai Chi practitioners were divided into a Master-level group (n = 8) and a first-class group (n = 8) according to official Chinese athlete certification. Kinematic, kinetic, and surface electromyography data were synchronously collected using a Vicon motion capture system, Kistler force platform, and wireless surface electromyography system. Estimated spinal segmental motor output, muscle synergy number and structure, co-contraction index (CI), center of activity (CoA), full width at half maximum (FWHM), and joint coordination parameters based on continuous relative phase (CRP) were quantified.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>Descriptive group-average profiles showed different temporal and rostrocaudal patterns of estimated lumbosacral motor output between groups. The participant-level mean number of muscle synergies did not differ significantly between the Master-level and first-class groups (3.73 \u00b1 0.37 vs. 3.63 \u00b1 0.33, p = 0.499). Three representative group-level synergy modules were identified in both groups, with module-specific differences in muscle-weighting composition. The CoA of matched M1 occurred significantly earlier in the Master-level group than in the first-class group (p = 0.004), whereas the CoA of M2 and M3 and the FWHM of all three modules did not differ significantly between groups. None of the four lower-limb co-contraction indices differed significantly between groups. Phase-level coordination analysis showed a more in-phase but more variable supporting-limb hip\u2013knee pattern during push-off and a more in-phase and less variable kicking-limb hip\u2013knee pattern during recovery in the Master-level group.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusion<\/jats:title>\n                    <jats:p>Greater motor experience was associated with selective and phase-specific differences in neuromuscular organization rather than with a general reduction in synergy number or co-contraction. The findings were characterized primarily by module-specific activation timing and phase-dependent hip\u2013knee coordination.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.3389\/fphys.2026.1873507","type":"journal-article","created":{"date-parts":[[2026,9,17]],"date-time":"2026-09-17T04:45:38Z","timestamp":1789620338000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":0,"title":["Neuromuscular control strategies during the Tai Chi heel-kick movement across different levels of motor experience"],"prefix":"10.3389","volume":"17","author":[{"given":"Ze","family":"Huang","sequence":"first","affiliation":[{"name":"Department of Physical Education, Wuhan Polytechnic University","place":["Wuhan, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Junyu","family":"Gao","sequence":"additional","affiliation":[{"name":"School of Physical Education, Chongqing University of Posts and Telecommunications","place":["Chongqing, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Luming","family":"Chen","sequence":"additional","affiliation":[{"name":"Department of Social Sports, School of Sports and Leisure, Guangdong Ocean University","place":["Zhanjiang, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xiaoshan","family":"Lei","sequence":"additional","affiliation":[{"name":"College of Physical Education and Sports, Beijing Normal University","place":["Beijing, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1965","published-online":{"date-parts":[[2026,9,17]]},"reference":[{"key":"B1","doi-asserted-by":"publisher","first-page":"1","DOI":"10.18637\/jss.v031.i10","article-title":"CircStat: a MATLAB toolbox for circular statistics","volume":"31","author":"Berens","year":"2009","journal-title":"J. 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