{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,23]],"date-time":"2026-07-23T11:25:41Z","timestamp":1784805941329,"version":"3.55.0"},"reference-count":48,"publisher":"MDPI AG","issue":"20","license":[{"start":{"date-parts":[[2022,10,14]],"date-time":"2022-10-14T00:00:00Z","timestamp":1665705600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJERPH"],"abstract":"<jats:p>Persistent quadriceps weakness after anterior cruciate ligament (ACL) reconstruction is a common hurdle to efficient rehabilitation. Therefore, we evaluated a new treatment strategy for athletes with ACL reconstruction. Eleven athletes with unilateral ACL reconstruction performed one set of flywheel Bulgarian split squats to exhaustion with a maximum knee extension of 60\u00b0, over 16 sessions, on their reconstructed limb. Quadriceps rate of force development (RFD) 0\u201350 ms (RFD0\u201350 ms), and 0\u2013150 ms (RFD0\u2013150 ms), maximum voluntary isometric contraction (MVIC), and central activation ratio (CAR) were measured bilaterally on the week before and after the intervention. In the reconstructed limb, the RFD0\u201350 ms (p = 0.04; Cohen\u2019s d = 0.8) and RFD0\u2013150 ms (p = 0.03; d = 0.9) increased after training. Before-after changes in MVIC and CAR were not significant (p &gt; 0.05), but the lower the baseline MVIC, the greater the gain in MVIC (r = \u22120.71, p = 0.02). The between-leg difference in MVIC changed from large before (p = 0.01; d = 0.8) to small after training (p = 0.04; d = 0.4). One set of deep knee flexion flywheel Bulgarian split squats to exhaustion improved quadriceps deficits in well-trained athletes with ACL-reconstruction, particularly those with relatively low quadriceps force production.<\/jats:p>","DOI":"10.3390\/ijerph192013209","type":"journal-article","created":{"date-parts":[[2022,10,17]],"date-time":"2022-10-17T00:04:55Z","timestamp":1665965095000},"page":"13209","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":6,"title":["Effects of 8-Week Exhausting Deep Knee Flexion Flywheel Training on Persistent Quadriceps Weakness in Well-Trained Athletes Following Anterior Cruciate Ligament Reconstruction"],"prefix":"10.3390","volume":"19","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-0269-5278","authenticated-orcid":false,"given":"Frederick James","family":"Henderson","sequence":"first","affiliation":[{"name":"Department of Health and Sport Management, Osaka University of Health and Sport Sciences, Sennan-gun 590-0496, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yu","family":"Konishi","sequence":"additional","affiliation":[{"name":"Department of Physical Education, National Defense Academy of Japan, Yokosuka 239-8686, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3471-6579","authenticated-orcid":false,"given":"Norihiro","family":"Shima","sequence":"additional","affiliation":[{"name":"Department of Sport and Health Science, Tokai Gakuen University, Miyoshi 470-0207, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2981-2470","authenticated-orcid":false,"given":"Yohei","family":"Shimokochi","sequence":"additional","affiliation":[{"name":"Department of Health and Sport Management, Osaka University of Health and Sport Sciences, Sennan-gun 590-0496, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2022,10,14]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"289","DOI":"10.1136\/bjsports-2017-098401","article-title":"Arthrogenic Muscle Inhibition after ACL Reconstruction: A Scoping Review of the Efficacy of Interventions","volume":"53","author":"Saithna","year":"2019","journal-title":"Br. 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