{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,28]],"date-time":"2026-07-28T17:34:05Z","timestamp":1785260045584,"version":"3.55.0"},"reference-count":39,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2021,3,9]],"date-time":"2021-03-09T00:00:00Z","timestamp":1615248000000},"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>Muscle coordination in human movement has been assessed through muscle synergy analysis. In sports science, this procedure has been mainly applied to the comparison between highly trained and unexperienced participants. However, the lack of knowledge regarding strength training exercises led us to study the differences in neural strategies to perform the power clean between weightlifters and untrained individuals. Synergies were extracted from electromyograms of 16 muscles of ten unexperienced participants and seven weightlifters. To evaluate differences, we determined the pairwise correlations for the synergy components and electromyographic profiles. While the shape of activation patterns presented strong correlations across participants of each group, the weightings of each muscle were more variable. The three extracted synergies were shifted in time with the unexperienced group anticipating synergy #1 (\u22122.46 \u00b1 18.7%; p &lt; 0.001) and #2 (\u22124.60 \u00b1 5.71%; p &lt; 0.001) and delaying synergy #3 (1.86 \u00b1 17.39%; p = 0.01). Moreover, muscle vectors presented more inter-group variability, changing the composition of synergy #1 and #3. These results may indicate an adaptation in intermuscular coordination with training, and athletes in an initial phase of training should attempt to delay the hip extension (synergy #1), as well as the upper-limb flexion (synergy #2).<\/jats:p>","DOI":"10.3390\/s21051904","type":"journal-article","created":{"date-parts":[[2021,3,9]],"date-time":"2021-03-09T06:22:32Z","timestamp":1615270952000},"page":"1904","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":14,"title":["Intermuscular Coordination in the Power Clean Exercise: Comparison between Olympic Weightlifters and Untrained Individuals\u2014A Preliminary Study"],"prefix":"10.3390","volume":"21","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-2074-722X","authenticated-orcid":false,"given":"Paulo D. G.","family":"Santos","sequence":"first","affiliation":[{"name":"Neuromuscular Research Lab, Faculty of Human Kinetics, Lisbon University, 1499-002 Cruz Quebrada-Dafundo, Portugal"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9691-5456","authenticated-orcid":false,"given":"Jo\u00e3o R.","family":"Vaz","sequence":"additional","affiliation":[{"name":"Neuromuscular Research Lab, Faculty of Human Kinetics, Lisbon University, 1499-002 Cruz Quebrada-Dafundo, Portugal"},{"name":"CIPER, Faculty of Human Kinetics, Lisbon University, 1499-002 Cruz Quebrada-Dafundo, Portugal"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1238-2566","authenticated-orcid":false,"given":"Paulo F.","family":"Correia","sequence":"additional","affiliation":[{"name":"Neuromuscular Research Lab, Faculty of Human Kinetics, Lisbon University, 1499-002 Cruz Quebrada-Dafundo, Portugal"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0983-1973","authenticated-orcid":false,"given":"Maria J.","family":"Valamatos","sequence":"additional","affiliation":[{"name":"Neuromuscular Research Lab, Faculty of Human Kinetics, Lisbon University, 1499-002 Cruz Quebrada-Dafundo, Portugal"},{"name":"CIPER, Faculty of Human Kinetics, Lisbon University, 1499-002 Cruz Quebrada-Dafundo, Portugal"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1068-1113","authenticated-orcid":false,"given":"Ant\u00f3nio P.","family":"Veloso","sequence":"additional","affiliation":[{"name":"CIPER, Faculty of Human Kinetics, Lisbon University, 1499-002 Cruz Quebrada-Dafundo, Portugal"},{"name":"Biomechanics and Functional Morphology Laboratory, Faculty of Human Kinetics, Lisbon University, 1499-002 Cruz Quebrada-Dafundo, Portugal"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6154-5563","authenticated-orcid":false,"given":"Pedro","family":"Pezarat-Correia","sequence":"additional","affiliation":[{"name":"Neuromuscular Research Lab, Faculty of Human Kinetics, Lisbon University, 1499-002 Cruz Quebrada-Dafundo, Portugal"},{"name":"CIPER, Faculty of Human Kinetics, Lisbon University, 1499-002 Cruz Quebrada-Dafundo, Portugal"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2021,3,9]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"145","DOI":"10.2165\/00007256-200737020-00004","article-title":"The adaptations to strength training: Morphological and neurological contributions to increased strength","volume":"37","author":"Folland","year":"2007","journal-title":"Sports Med."},{"key":"ref_2","first-page":"115","article-title":"Neural factors versus hypertrophy in the time course of muscle strength gain","volume":"58","author":"Moritani","year":"1979","journal-title":"Am. J. Phys. Med."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"S135","DOI":"10.1249\/00005768-198810001-00009","article-title":"Neural adaptation to resistance training","volume":"20","author":"Sale","year":"1988","journal-title":"Med. Sci. Sports Exerc."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"1766","DOI":"10.1152\/japplphysiol.00543.2006","article-title":"Training adaptations in the behavior of human motor units","volume":"101","author":"Duchateau","year":"2006","journal-title":"J. Appl. Physiol."},{"key":"ref_5","doi-asserted-by":"crossref","unstructured":"Komi, P.V. (2003). Neural Adaptation to Strength Training. Strength and Power in Sport, Wiley-Blackwell. [2nd ed.].","DOI":"10.1002\/9780470757215"},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"328","DOI":"10.1139\/h05-125","article-title":"Resistance training: Cortical, spinal, and motor unit adaptations","volume":"30","author":"Griffin","year":"2005","journal-title":"Can. J. Appl. Physiol."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"1341","DOI":"10.1152\/jappl.1998.84.4.1341","article-title":"Changes in agonist-antagonist EMG, muscle CSA, and force during strength training in middle-aged and older people","volume":"84","author":"Kallinen","year":"1998","journal-title":"J. Appl. Physiol."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"769","DOI":"10.1007\/BF03262294","article-title":"Unique aspects of competitive weightlifting: Performance, training and physiology","volume":"42","author":"Storey","year":"2012","journal-title":"Sports Med."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"2192","DOI":"10.1519\/JSC.0b013e31823b087a","article-title":"Olympic weightlifting training causes different knee muscle-coactivation adaptations compared with traditional weight training","volume":"26","author":"Arabatzi","year":"2012","journal-title":"J. Strength Cond. Res."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"348","DOI":"10.1111\/sms.13331","article-title":"Neural adaptations after 4 years vs 12 weeks of resistance training vs untrained","volume":"29","author":"Balshaw","year":"2019","journal-title":"Scand. J. Med. Sci. Sports"},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"16","DOI":"10.1310\/sci1701-16","article-title":"Muscle Synergies: Implications for Clinical Evaluation and Rehabilitation of Movement","volume":"17","author":"Safavynia","year":"2011","journal-title":"Top. Spinal Cord. Inj. Rehabil."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"622","DOI":"10.1016\/j.conb.2008.01.002","article-title":"Neuromechanics of muscle synergies for posture and movement","volume":"17","author":"Ting","year":"2007","journal-title":"Curr. Opin. Neurobiol."},{"key":"ref_13","unstructured":"Leen, T.K., Dietterich, T.G., and Tresp, V. (2001). Algorithms for non-negative matrix factorization. Advances in Neural Information Processing Systems 13, MIT Press."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"51","DOI":"10.3389\/fncom.2013.00051","article-title":"The neural origin of muscle synergies","volume":"7","author":"Bizzi","year":"2013","journal-title":"Front. Comput. Neurosci."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1016\/j.jelekin.2010.08.009","article-title":"Can muscle coordination be precisely studied by surface electromyography?","volume":"21","author":"Hug","year":"2011","journal-title":"J. Electromyogr. Kinesiol."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"3426","DOI":"10.1152\/jn.00081.2006","article-title":"Motor patterns in human walking and running","volume":"95","author":"Cappellini","year":"2006","journal-title":"J. Neurophysiol."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"319","DOI":"10.1080\/02640414.2017.1306090","article-title":"Specific muscle synergies in national elite female ice hockey players in response to unexpected external perturbation","volume":"36","author":"Kim","year":"2018","journal-title":"J. Sports Sci."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"91","DOI":"10.1152\/jn.01096.2010","article-title":"Consistency of muscle synergies during pedaling across different mechanical constraints","volume":"106","author":"Hug","year":"2011","journal-title":"J. Neurophysiol."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"1727","DOI":"10.1152\/japplphysiol.01305.2009","article-title":"Is interindividual variability of EMG patterns in trained cyclists related to different muscle synergies?","volume":"108","author":"Hug","year":"2010","journal-title":"J. Appl. Physiol."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"1030","DOI":"10.1016\/j.jelekin.2011.07.013","article-title":"No evidence of expertise-related changes in muscle synergies during rowing","volume":"21","author":"Turpin","year":"2011","journal-title":"J. Electromyogr. Kinesiol."},{"key":"ref_21","first-page":"99","article-title":"Between-subject variability of muscle synergies during a complex motor skill","volume":"6","author":"Hug","year":"2012","journal-title":"Front. Comput. Neurosci."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"1941","DOI":"10.1080\/02640414.2016.1143109","article-title":"Muscle coordination during breaststroke swimming: Comparison between elite swimmers and beginners","volume":"34","author":"Vaz","year":"2016","journal-title":"J. Sports Sci."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"89","DOI":"10.1111\/sms.12167","article-title":"Inter-subject variability of muscle synergies during bench press in power lifters and untrained individuals","volume":"25","author":"Kristiansen","year":"2015","journal-title":"Scand. J. Med. Sci. Sports"},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"6592357","DOI":"10.1155\/2018\/6592357","article-title":"Comparison of Modular Control during Smash Shot between Advanced and Beginner Badminton Players","volume":"2018","author":"Matsunaga","year":"2018","journal-title":"Appl. Bionics Biomech."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"145","DOI":"10.1016\/j.jelekin.2011.10.001","article-title":"Catapult effect in pole vaulting: Is muscle coordination determinant?","volume":"22","author":"Hug","year":"2012","journal-title":"J. Electromyogr. Kinesiol."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"1948","DOI":"10.1519\/JSC.0000000000001282","article-title":"Effects of 5 Weeks of Bench Press Training on Muscle Synergies: A Randomized Controlled Study","volume":"30","author":"Kristiansen","year":"2016","journal-title":"J. Strength Cond. Res."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"972","DOI":"10.1111\/sms.13027","article-title":"Effects of wobble board training on single-leg landing neuromechanics","volume":"28","author":"Silva","year":"2018","journal-title":"Scand. J. Med. Sci. Sports"},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"1210","DOI":"10.1519\/JSC.0b013e3182679364","article-title":"Within- and between-session reliability of power, force, and rate of force development during the power clean","volume":"27","author":"Comfort","year":"2013","journal-title":"J. Strength Cond. Res."},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"3089","DOI":"10.1519\/JSC.0000000000000815","article-title":"Reliability of Maximal Back Squat and Power Clean Performances in Inexperienced Athletes","volume":"29","author":"Comfort","year":"2015","journal-title":"J. Strength Cond. Res."},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"432","DOI":"10.1519\/JSC.0b013e318220db2c","article-title":"Reliability of the one-repetition-maximum power clean test in adolescent athletes","volume":"26","author":"Faigenbaum","year":"2012","journal-title":"J. Strength Cond. Res."},{"key":"ref_31","doi-asserted-by":"crossref","unstructured":"Santos, P.D.G., Vaz, J.R., Correia, P.F., Valamatos, M.J., Veloso, A.P., and Pezarat-Correia, P. (2020). Muscle Synergies Reliability in the Power Clean Exercise. J. Funct. Morphol. Kinesiol, 5.","DOI":"10.3390\/jfmk5040075"},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"41","DOI":"10.1007\/BF00952243","article-title":"Recommendations for the standardization of lead positions in surface electromyography","volume":"50","author":"Zipp","year":"1982","journal-title":"Eur. J. Appl. Physiol."},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"137","DOI":"10.1007\/s00276-007-0289-y","article-title":"Anatomical optimization of skin electrode placement to record electromyographic activity of erector spinae muscles","volume":"30","author":"Cazalets","year":"2008","journal-title":"Surg. Radiol. Anat."},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"361","DOI":"10.1016\/S1050-6411(00)00027-4","article-title":"Development of recommendations for SEMG sensors and sensor placement procedures","volume":"10","author":"Hermens","year":"2000","journal-title":"J. Electromyogr. Kinesiol."},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"244","DOI":"10.1152\/jn.00557.2014","article-title":"Effect of acute noxious stimulation to the leg or back on muscle synergies during walking","volume":"113","author":"Hodges","year":"2015","journal-title":"J. Neurophysiol."},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"1480","DOI":"10.1016\/j.humov.2013.07.018","article-title":"Inter-individual variability of forces and modular muscle coordination in cycling: A study on untrained subjects","volume":"32","author":"Schmid","year":"2013","journal-title":"Hum. Mov. Sci."},{"key":"ref_37","doi-asserted-by":"crossref","first-page":"276","DOI":"10.1123\/mcj.11.3.276","article-title":"Toward a New Theory of Motor Synergies","volume":"11","author":"Latash","year":"2007","journal-title":"Motor Control"},{"key":"ref_38","doi-asserted-by":"crossref","first-page":"14652","DOI":"10.1073\/pnas.1212056109","article-title":"Muscle synergy patterns as physiological markers of motor cortical damage","volume":"109","author":"Cheung","year":"2012","journal-title":"Proc. Natl. Acad. Sci. USA"},{"key":"ref_39","doi-asserted-by":"crossref","first-page":"3076","DOI":"10.1073\/pnas.0500199102","article-title":"Shared and specific muscle synergies in natural motor behaviors","volume":"102","author":"Bizzi","year":"2005","journal-title":"Proc. Natl. Acad. Sci. USA"}],"container-title":["Sensors"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1424-8220\/21\/5\/1904\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T05:35:18Z","timestamp":1760160918000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1424-8220\/21\/5\/1904"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2021,3,9]]},"references-count":39,"journal-issue":{"issue":"5","published-online":{"date-parts":[[2021,3]]}},"alternative-id":["s21051904"],"URL":"https:\/\/doi.org\/10.3390\/s21051904","relation":{},"ISSN":["1424-8220"],"issn-type":[{"value":"1424-8220","type":"electronic"}],"subject":[],"published":{"date-parts":[[2021,3,9]]}}}