{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,5,14]],"date-time":"2025-05-14T02:13:20Z","timestamp":1747188800609,"version":"3.40.5"},"reference-count":26,"publisher":"Human Kinetics","issue":"10","content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2024,10,1]]},"abstract":"<jats:p><jats:italic><jats:bold>Purpose<\/jats:bold>:<\/jats:italic> To compare the effects of 6-week barbell weighted-jump-squat (WJS) training with and without eccentric load reduction on explosive performance. <jats:italic><jats:bold>Methods<\/jats:bold>:<\/jats:italic> Twenty well-trained male athletes were randomly assigned to either an experimental group (n\u2009=\u200910) or a control group (n\u2009=\u200910). Participants completed 12 WJS training sessions (6 sets of 5 repetitions of barbell back squat at 30% of 1-repetition maximum\u00a0[1RM]) twice a week over a 6-week period. While the\u00a0control group used 0% eccentric loading (ie,\u00a0traditional WJS), the\u00a0experimental group utilized a 50% eccentric loading reduction with a mechanical braking unit (ie,\u00a0eccentric load set at 15% of 1RM). Performance assessments, including countermovement jump, 20-m sprint, standing long jump, and 1RM barbell back squat, were conducted both before (pretests) and after (posttests) the intervention. <jats:italic><jats:bold>Results<\/jats:bold>:<\/jats:italic> Both the\u00a0experimental group and the\u00a0control group demonstrated a significant increase in countermovement-jump height (+6.4%\u2009[4.0%] vs +4.9%\u2009[5.7%]; <jats:italic>P<\/jats:italic>\u2009&lt;\u2009.001) and peak power output (+2.3%\u2009[2.7%] vs +1.9%\u2009[5.1%]; <jats:italic>P<\/jats:italic>\u2009=\u2009.017), faster 20-m sprint times (+9.4%\u2009[4.8%] vs +9.2%\u2009[5.5%]; <jats:italic>P<\/jats:italic>\u2009&lt;\u2009.001), longer standing long jump (+3.1%\u2009[2.5%] vs +3.0%\u2009[3.3%]; <jats:italic>P<\/jats:italic>\u2009&lt;\u2009.001), and higher 1RM back squat (+6.4%\u2009[4.0%] vs +4.9%\u2009[5.7%]; <jats:italic>P<\/jats:italic>\u2009&lt;\u2009.001) from pretests to posttests. However, there was no significant condition\u2009\u00d7\u2009time interaction for any variable (all <jats:italic>P<\/jats:italic>\u2009\u2265\u2009.294). <jats:italic><jats:bold>Conclusions<\/jats:bold>:<\/jats:italic> Both WJS training methods, with and without load reduction in the eccentric phase, effectively enhance explosive performance. Nevertheless, athletes in later stages of injury rehabilitation or intense training may find reducing eccentric load a more tolerable strategy for achieving similar performance gains compared with traditional isoinertial loading.<\/jats:p>","DOI":"10.1123\/ijspp.2024-0071","type":"journal-article","created":{"date-parts":[[2024,8,22]],"date-time":"2024-08-22T00:04:26Z","timestamp":1724285066000},"page":"1115-1121","source":"Crossref","is-referenced-by-count":0,"title":["Effects of 6-Week Weighted-Jump-Squat Training With and Without Eccentric Load Reduction on Explosive Performance"],"prefix":"10.1123","volume":"19","author":[{"given":"Baoyi","family":"Yi","sequence":"first","affiliation":[{"name":"China Institute of Sport and Health Science, Beijing Sport University, Beijing, China"},{"name":"Department of Physical Education and Research, Yanzhou High School of Zhongshan, Zhongshan, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1709-8297","authenticated-orcid":true,"given":"Liang","family":"Zhang","sequence":"additional","affiliation":[{"name":"School of Strength and Conditioning Training, Beijing Sport University, Beijing, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Conghui","family":"Zhang","sequence":"additional","affiliation":[{"name":"China Institute of Sport and Health Science, Beijing Sport University, Beijing, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Tian","family":"Huang","sequence":"additional","affiliation":[{"name":"China Institute of Sport and Health Science, Beijing Sport University, Beijing, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yang","family":"Wang","sequence":"additional","affiliation":[{"name":"China Institute of Sport and Health Science, Beijing Sport University, Beijing, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Xinrong","family":"Zhao","sequence":"additional","affiliation":[{"name":"School of Strength and Conditioning Training, Beijing Sport University, Beijing, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0951-9186","authenticated-orcid":true,"given":"Bing","family":"Yan","sequence":"additional","affiliation":[{"name":"China Institute of Sport and Health Science, Beijing Sport University, Beijing, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4797-182X","authenticated-orcid":true,"given":"Olivier","family":"Girard","sequence":"additional","affiliation":[{"name":"School of Human Sciences (Exercise and Sport Science), University of Western Australia, Perth, WA, Australia"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"100","reference":[{"issue":"8","key":"r1","series-title":"Med Sci Sports Exerc","doi-asserted-by":"publisher","first-page":"1582","DOI":"10.1249\/MSS.0b013e3181d2013a","article-title":"Adaptations in athletic performance after ballistic power vs strength training","volume":"42","author":"Cormie P","year":"2010","unstructured":"Cormie P, McGuigan MR, Newton RU. 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