{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,11,12]],"date-time":"2026-11-12T06:37:45Z","timestamp":1794465465039,"version":"4.9.1"},"reference-count":32,"publisher":"Human Kinetics","content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2026]]},"abstract":"<jats:p>Single-leg hop performance is widely used in clinics to assess knee function following anterior cruciate ligament injury. However, performance provides limited insight into joint-specific kinetic contributions, and the influence of repeated trials remains unclear. This study quantified the effects of hop directions (forward\/vertical\/backward) and repeated practice trials on performance and lower-limb joint kinetics. Forty-five injury-free participants performed 10 trials per task. Hop performance and peak moment\/power\/work at the hip\/knee\/ankle were calculated. Trials were grouped as one practice attempt and 3 blocks: I (trials 2\u20134), II (trials 5\u20137), and III (trials 8\u201310). Three-by-three repeated-measures analyses of variance were conducted to quantify the effects of task and practice. Backward hop demonstrated the greatest knee moment\/work\/power and contribution across blocks. Performance increased across blocks in forward and backward hops while remaining consistent in the vertical hop. Knee work was smaller in block I across tasks, whereas backward hop demonstrated greater knee work contribution in block II than in block I. The backward hop places greater knee emphasis, supporting its use as a knee-specific assessment. Minimal practice trials are necessary when using forward\/vertical\/backward hop performance to assess knee power, whereas at least 4 trials may be required for forward and vertical hops when evaluating knee work.<\/jats:p>","DOI":"10.1123\/jab.2026-0051","type":"journal-article","created":{"date-parts":[[2026,10,16]],"date-time":"2026-10-16T01:38:18Z","timestamp":1792114698000},"page":"1-13","source":"Crossref","is-referenced-by-count":0,"title":["Optimizing Clinical Assessment of Knee Function: Biomechanical Adaptations Across Repeated Single-Leg Hop Trials"],"prefix":"10.1123","author":[{"given":"Yu","family":"Gu","sequence":"first","affiliation":[{"name":"Department of Health, Sport & Exercise Sciences, The University of Kansas, Lawrence, KS, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0007-4479-346X","authenticated-orcid":true,"given":"Wanyan","family":"Su","sequence":"additional","affiliation":[{"name":"Department of Health, Sport & Exercise Sciences, The University of Kansas, Lawrence, KS, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Nawfal","family":"Malik","sequence":"additional","affiliation":[{"name":"Department of Health, Sport & Exercise Sciences, The University of Kansas, Lawrence, KS, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Thanh","family":"Nguyen","sequence":"additional","affiliation":[{"name":"Department of Health, Sport & Exercise Sciences, The University of Kansas, Lawrence, KS, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2140-3656","authenticated-orcid":true,"given":"Xianglin","family":"Wan","sequence":"additional","affiliation":[{"name":"School of Sport Science, Beijing Sport University, Beijing, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9525-2870","authenticated-orcid":true,"given":"Yu","family":"Song","sequence":"additional","affiliation":[{"name":"Department of Health, Sport & Exercise Sciences, The University of Kansas, Lawrence, KS, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"100","reference":[{"issue":"10","key":"r1","series-title":"Am J Sports Med","doi-asserted-by":"publisher","first-page":"2363","DOI":"10.1177\/0363546514542796","article-title":"Incidence and trends of anterior cruciate ligament reconstruction in the United States","volume":"42","author":"Mall NA","year":"2014","unstructured":"Mall NA, Chalmers PN, Moric M, et\u00a0al. 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