{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,24]],"date-time":"2026-06-24T06:47:22Z","timestamp":1782283642038,"version":"3.54.5"},"reference-count":31,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2026,6,24]],"date-time":"2026-06-24T00:00:00Z","timestamp":1782259200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Sports Act. Living"],"abstract":"<jats:sec>\n                    <jats:title>Objective<\/jats:title>\n                    <jats:p>The primary objective of this study is to investigate the effects and biomechanical mechanisms of early gait retraining (GRT) on knee cartilage degeneration following anterior cruciate ligament reconstruction (ACLR).<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>\n                      This study is a single-blind, parallel-group randomized controlled trial. A total of 60 participants scheduled for primary unilateral ACLR will be recruited and randomly allocated to either the experimental group (conventional rehabilitation plus gait retraining) or the control group (conventional rehabilitation only). Gait retraining will commence at 3 weeks post-surgery, lasting for 6 weeks with a frequency of 2\u20133 sessions per week, each lasting 15\u201320\u2005min. Data will be collected at baseline (pre-intervention) and at 3 months, 6 months, 1 year, and 2 years postoperatively. Assessment will include three-dimensional gait analysis, surface electromyography (sEMG), isokinetic muscle strength testing, functional magnetic resonance imaging (fMRI), Y-balance test, single-leg hop test, the International Knee Documentation Committee (IKDC) subjective knee evaluation form, Lysholm knee score, and Tegner activity scale. The primary outcome measure is the peak knee flexion moment during walking. Secondary outcomes include cartilage T1\n                      <jats:italic>\u03c1<\/jats:italic>\n                      \/T2 values, muscle activation patterns, and subjective functional scores. A repeated-measures analysis of variance (ANOVA) will be used to evaluate the intervention effects on the outcome measures.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>Not applicable.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusion<\/jats:title>\n                    <jats:p>Early gait retraining using a lower-body positive pressure (anti-gravity) treadmill after ACLR is hypothesized to significantly improve postoperative gait biomechanics. Furthermore, early GRT may optimize standard rehabilitation protocols, potentially preventing or delaying cartilage degeneration. This approach holds clinical significance for restoring normal gait and preventing secondary injuries in individuals with sports-related injuries.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Clinical Trial Registration<\/jats:title>\n                    <jats:p>\n                      <jats:ext-link>https:register.clinicaltrials.gov<\/jats:ext-link>\n                      , identifier NCT06368544\n                    <\/jats:p>\n                  <\/jats:sec>","DOI":"10.3389\/fspor.2026.1833258","type":"journal-article","created":{"date-parts":[[2026,6,24]],"date-time":"2026-06-24T05:55:43Z","timestamp":1782280543000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":0,"title":["Biomechanical mechanisms of early gait training on knee cartilage degeneration after anterior cruciate ligament reconstruction: a study 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Institute of Sports Medicine of Peking University","place":["Beijing, China"]},{"name":"Beijing Key Laboratory of Research and Translation for Drugs and Medical Devices in Precision Diagnosis and Treatment of Sports Injuries","place":["Beijing, China"]},{"name":"Engineering Research Center of Sports Trauma Treatment Technology and Devices, Ministry of Education","place":["Beijing, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jianquan","family":"Wang","sequence":"additional","affiliation":[{"name":"Department of Sports Medicine, Peking University Third Hospital, Institute of Sports Medicine of Peking University","place":["Beijing, China"]},{"name":"Beijing Key Laboratory of Research and Translation for Drugs and Medical Devices in Precision Diagnosis and Treatment of Sports Injuries","place":["Beijing, China"]},{"name":"Engineering Research Center of Sports Trauma Treatment Technology and Devices, Ministry of Education","place":["Beijing, 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