{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,22]],"date-time":"2026-09-22T05:04:23Z","timestamp":1790053463452,"version":"4.0.1"},"reference-count":48,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2026,9,22]],"date-time":"2026-09-22T00:00:00Z","timestamp":1790035200000},"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. Physiol."],"abstract":"<jats:sec>\n                    <jats:title>Introduction<\/jats:title>\n                    <jats:p>This study investigated the effects of carbon dioxide hydrate (CDH) cryotherapy on the recovery trajectories of muscle function and physiological markers following exercise-induced muscle damage (EIMD) of the knee flexors.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>In a randomized parallel-group design, 24 young men were assigned to the CDH, conventional icing (ICE), or non-intervention control (CON) group (n = 8 per group). To induce muscle damage, participants performed 10 sets of eight maximal eccentric contractions of the knee flexors in a prone position (knee joint range: 75\u00b0\u201315\u00b0 of flexion at 60\u00b0\/s; 0\u00b0 = the fully extended anatomical position). Maximal voluntary isometric contraction (MVIC) torque of the knee flexors was measured at 30\u00b0 of knee flexion at baseline (PRE), immediately post-exercise (POST), and at 4.5, 24, 48, 72, and 168\u00a0h post-exercise. Secondary outcomes, including thigh circumference, hip joint range of motion (ROM), and hamstring muscle stiffness and pressure-induced soreness were assessed at all time points except POST. A 20-min intervention was administered after each assessment from POST to 72\u00a0h.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>\n                      Linear mixed-effects models, adjusted for PRE values, revealed no significant group \u00d7 time interactions for changes from PRE in any outcome across post-exercise time points (POST to 168\u00a0h for MVIC torque; 4.5 to 168\u00a0h for secondary outcomes;\n                      <jats:italic>p<\/jats:italic>\n                      \u00a0=\u00a00.177\u20130.914). A significant main effect of group was observed only for hip joint ROM (\n                      <jats:italic>p<\/jats:italic>\n                      \u00a0=\u00a00.039).\n                      <jats:italic>Post-hoc<\/jats:italic>\n                      comparisons revealed a significantly greater overall reduction from PRE in the CDH group than in the CON group (difference: 10.3\u00b0, 95% CI: 3.0\u00b0 to 17.6\u00b0,\n                      <jats:italic>p<\/jats:italic>\n                      \u00a0=\u00a00.017), with no significant differences between the other group pairs (both\n                      <jats:italic>p<\/jats:italic>\n                      \u00a0=\u00a00.131). Given the multi-outcome testing, this isolated effect should be interpreted as exploratory.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusion<\/jats:title>\n                    <jats:p>Under the present experimental conditions, CDH cryotherapy did not accelerate the recovery of muscle function or attenuate secondary markers following EIMD relative to conventional icing or no intervention.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.3389\/fphys.2026.1924770","type":"journal-article","created":{"date-parts":[[2026,9,22]],"date-time":"2026-09-22T04:23:14Z","timestamp":1790050994000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":0,"title":["Effects of carbon dioxide hydrate cryotherapy on knee flexor muscle function recovery trajectory after muscle damage: a randomized controlled trial"],"prefix":"10.3389","volume":"17","author":[{"given":"Rina","family":"Watabe","sequence":"first","affiliation":[{"name":"Graduate School of Engineering and Science, Shibaura Institute of Technology","place":["Saitama, Japan"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Daigo","family":"Shiozaki","sequence":"additional","affiliation":[{"name":"Graduate School of Engineering and Science, Shibaura Institute of Technology","place":["Saitama, Japan"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kohei","family":"Ono","sequence":"additional","affiliation":[{"name":"Department of Psychology, Columbia University","place":["New York, NY, United States"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kosuke","family":"Hirata","sequence":"additional","affiliation":[{"name":"Institute of Health and Sport Sciences, University of Tsukuba","place":["Tsukuba, Japan"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ryota","family":"Akagi","sequence":"additional","affiliation":[{"name":"Graduate School of Engineering and Science, Shibaura Institute of Technology","place":["Saitama, Japan"]},{"name":"Sports Engineering Course, Bioscience and Engineering Program, College of Systems Engineering and Science, Shibaura Institute of Technology","place":["Saitama, Japan"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1965","published-online":{"date-parts":[[2026,9,22]]},"reference":[{"key":"B1","doi-asserted-by":"publisher","first-page":"2209","DOI":"10.1080\/02640414.2024.2318540","article-title":"Eight-week neuromuscular electrical stimulation training produces muscle strength gains and hypertrophy, and partial muscle quality improvement in the knee extensors","volume":"41","author":"Akagi","year":"2024","journal-title":"J. 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