{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,1]],"date-time":"2026-10-01T20:19:16Z","timestamp":1790885956015,"version":"4.1.0"},"reference-count":59,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2026,8,17]],"date-time":"2026-08-17T00:00:00Z","timestamp":1786924800000},"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>Background<\/jats:title>\n                    <jats:p>Unilateral training may enhance sprint and change-of-direction (COD) performance in athletes, but existing evidence is inconclusive.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>We searched CNKI, PubMed, Web of Science, and EBSCO up to 1 September 2025 for randomized controlled trials comparing unilateral versus bilateral training in athletes and reporting speed-related outcomes. Methodological quality was assessed with PEDro. Random-effects meta-analyses computed mean differences (MD), and GRADE was used for certainty grading.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>\n                      Fourteen studies (415 male athletes, aged 9\u201327 years) were included. Unilateral training showed no significant pooled effects on 10\u00a0m, 20-m, or 30\u00a0m sprints (overall\n                      <jats:italic>I\u00b2<\/jats:italic>\n                      \u00a0=\u00a058%), the T-test (\n                      <jats:italic>I\u00b2<\/jats:italic>\n                      \u00a0=\u00a059%), or COD to the right (COD-R,\n                      <jats:italic>I\u00b2<\/jats:italic>\n                      \u00a0=\u00a044%). The 505 test was not pooled because of very high heterogeneity (\n                      <jats:italic>I\u00b2<\/jats:italic>\n                      \u00a0=\u00a092%) and conflicting individual findings. Significant improvements favoring unilateral training were observed for 5\u00a0m sprint (Z\u00a0=\u00a02.01,\n                      <jats:italic>P<\/jats:italic>\n                      \u00a0=\u00a00.04) and COD to the left (COD-L, Z\u00a0=\u00a02.13,\n                      <jats:italic>P<\/jats:italic>\n                      \u00a0=\u00a00.03). Age subgroup analysis (&amp;lt;18 vs. \u226518 years) did not moderate 10\u00a0m sprint results (\n                      <jats:italic>P<\/jats:italic>\n                      =\u00a00.64). Overall evidence quality was low to moderate.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusion<\/jats:title>\n                    <jats:p>Unilateral training confers selective, small-magnitude benefits for 5\u00a0m sprint and COD-L, but these results are preliminary. The COD-L finding rests on only three studies (63 athletes), and the 5-m finding on four studies (113 athletes). Given the exclusively male sample and wide age range (9\u201327 years), generalization requires caution. Unilateral training did not universally improve all sprint or COD measures. While results for 30-m sprint, T-test, and COD-R were relatively consistent, the 505-test evidence should be interpreted with caution because of high heterogeneity. Future large-scale RCTs should explore applicability across sports, age groups, and sexes, with attention to maturational status and training age in younger populations.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Systematic Review Registration<\/jats:title>\n                    <jats:p>\n                      <jats:ext-link>https:\/\/www.crd.york.ac.uk\/prospero\/display_record.php?RecordID=1031255<\/jats:ext-link>\n                      , identifier CRD420251031255.\n                    <\/jats:p>\n                  <\/jats:sec>","DOI":"10.3389\/fphys.2026.1884017","type":"journal-article","created":{"date-parts":[[2026,8,17]],"date-time":"2026-08-17T04:32:09Z","timestamp":1786941129000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":1,"title":["Effects of unilateral versus bilateral training on linear sprint and change-of-direction performance in athletes: a systematic review and meta-analysis"],"prefix":"10.3389","volume":"17","author":[{"given":"Chen","family":"Dong","sequence":"first","affiliation":[{"name":"School of Physical Education, Xi\u2019an Petroleum University Xi\u2019an","place":["Shaanxi, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yugang","family":"Zhang","sequence":"additional","affiliation":[{"name":"Department of Physical Education, Yuncheng University","place":["Yuncheng, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Min","family":"Sun","sequence":"additional","affiliation":[{"name":"School of Physical Education, Baoshan University","place":["Baoshan, Yunnan, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1965","published-online":{"date-parts":[[2026,8,17]]},"reference":[{"key":"B20","doi-asserted-by":"publisher","first-page":"318","DOI":"10.1519\/JSC.0000000000002923","article-title":"Specificity and transfer of lower-body strength: influence of bilateral or unilateral lower-body resistance training","volume":"33","author":"Appleby","year":"2019","journal-title":"J. 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