{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,25]],"date-time":"2026-10-25T10:54:03Z","timestamp":1792925643943,"version":"4.5.0"},"reference-count":49,"publisher":"Public Library of Science (PLoS)","issue":"8","license":[{"start":{"date-parts":[[2024,8,7]],"date-time":"2024-08-07T00:00:00Z","timestamp":1722988800000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["www.plosone.org"],"crossmark-restriction":false},"short-container-title":["PLoS ONE"],"abstract":"<jats:p>Barbell squats are commonly utilized in resistance training for rehabilitation, daily living enhancement, and improving sports performance. The current study investigated the kinematic and electromyographic (EMG) parameters in the squat between sexes across different repetition ranges (1-, 3-, 6-, and 10-RM) among recreationally strength-trained subjects. A total of 26 subjects (13 men: age 25 \u00b1 3.5 years, height 178.2 \u00b1 5.8 cm, weight 82.3 \u00b1 9.1 kg; 13 women: age 24 \u00b1 4.1 years, height 165.4 \u00b1 6.3 cm, weight 68.2 \u00b1 8.7 kg) participated in the study. The level of significance was set at p&lt;0.05. The findings revealed no sex-specific differences in average barbell velocity across repetition ranges. However, the 1-RM showed a significantly lower average velocity compared to the final repetition of other repetition ranges (p&lt;0.001), with the last repetition at 10-RM revealing a significantly higher velocity (p&lt;0.001). Women had greater maximal angular hip extension velocity in the final repetitions of the 6- and 10-RM (p\u22640.035, \u03b7<jats:sub>p<\/jats:sub><jats:sup>2<\/jats:sup>\u22640.20), while both sexes displayed lower maximal angular knee extension velocity in the final repetition of the 10-RM (p = 0.028, \u03b7p<jats:sup>2<\/jats:sup> = 0.15). Moreover, men had lower EMG amplitude in the rectus femoris (3- and 10-RM), soleus, and lateral vastus (10-RM) compared to women (p\u22650.011, \u03b7p<jats:sup>2<\/jats:sup>\u22650.26). It was concluded that 10-RM differed greatly in kinematics and EMG, suggesting different fatigue mechanisms compared to other repetition ranges with heavier loads. Furthermore, sex differences in EMG and angular hip extension velocity might imply sex-specific fatiguing mechanisms during high-repetition squats. These considerations could be important when prescribing training programs.<\/jats:p>","DOI":"10.1371\/journal.pone.0308344","type":"journal-article","created":{"date-parts":[[2024,8,7]],"date-time":"2024-08-07T17:28:33Z","timestamp":1723051713000},"page":"e0308344","update-policy":"https:\/\/doi.org\/10.1371\/journal.pone.corrections_policy","source":"Crossref","is-referenced-by-count":5,"title":["Sex differences in intra-set kinematics and electromyography during different maximum repetition sets in the barbell back squat?"],"prefix":"10.1371","volume":"19","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-4481-4490","authenticated-orcid":true,"given":"Roland","family":"van den Tillaar","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0002-8968-3081","authenticated-orcid":true,"given":"Andrea","family":"Bao Fredriksen","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Andreas","family":"Hegdahl Gundersen","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hallvard","family":"Nygaard Falch","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"340","published-online":{"date-parts":[[2024,8,7]]},"reference":[{"issue":"4","key":"pone.0308344.ref001","doi-asserted-by":"crossref","first-page":"1169","DOI":"10.1519\/JSC.0b013e31822d533d","article-title":"Muscle activation in the loaded free barbell squat: a brief review","volume":"26","author":"DR Clark","year":"2012","journal-title":"The Journal of Strength & Conditioning Research"},{"issue":"2","key":"pone.0308344.ref002","doi-asserted-by":"crossref","first-page":"32","DOI":"10.3390\/sports9020032","article-title":"Loading recommendations for muscle strength, hypertrophy, and local endurance: a re-examination of the repetition continuum","volume":"9","author":"BJ Schoenfeld","year":"2021","journal-title":"Sports"},{"issue":"4","key":"pone.0308344.ref003","doi-asserted-by":"crossref","first-page":"7","DOI":"10.1519\/0744-0049(1993)015<0007:EEAT>2.3.CO;2","article-title":"Explosive exercise","volume":"15","author":"M Stone","year":"1993","journal-title":"Nat Strength Cond Assoc J"},{"key":"pone.0308344.ref004","doi-asserted-by":"crossref","first-page":"202","DOI":"10.1016\/j.jshs.2021.01.007","article-title":"Effects of resistance training performed to repetition failure or non-failure on muscular strength and hypertrophy: a systematic review and meta-analysis","volume":"11","author":"J Grgic","year":"2021","journal-title":"Journal of Sport and Health Science"},{"issue":"5","key":"pone.0308344.ref005","doi-asserted-by":"crossref","first-page":"108","DOI":"10.1519\/SSC.0000000000000473","article-title":"Does training to failure maximize muscle hypertrophy?","volume":"41","author":"BJ Schoenfeld","year":"2019","journal-title":"Strength & Conditioning Journal"},{"issue":"1","key":"pone.0308344.ref006","doi-asserted-by":"crossref","first-page":"34","DOI":"10.1519\/SSC.0b013e3182079cdf","article-title":"The science and practice of periodization: a brief review","volume":"33","author":"A. 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