{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T20:40:54Z","timestamp":1760128854754,"version":"build-2065373602"},"reference-count":35,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2023,6,23]],"date-time":"2023-06-23T00:00:00Z","timestamp":1687478400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"National Sports Institute of Malaysia","award":["ISNRG 001\/2020"],"award-info":[{"award-number":["ISNRG 001\/2020"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Symmetry"],"abstract":"<jats:p>Studies evaluating mechanical asymmetry across a range of running velocities during treadmill runs have yielded inconsistent findings, while the impact of additional hypoxic exposure has never been investigated. The aim of this study was to characterize the effects of manipulating running velocity and hypoxic exposure on gait asymmetry during treadmill running. Eleven trained individuals performed seven runs at different velocities (8, 10, 12, 14, 16, 18, and 20 km\u00b7h\u22121) in a randomized order, each lasting 45 s. The running took place on an instrumented treadmill for normoxia (FiO2 = 20.9%), moderate hypoxia (FiO2 = 16.1%), high hypoxia (FiO2 = 14.1%), and severe hypoxia (FiO2 = 13.0%). Vertical and antero-posterior ground reaction force recordings over 20 consecutive steps (i.e., after running \u223c25 s) allowed the measurement of running mechanics. Lower-limb asymmetry was assessed from the \u2018symmetry angle\u2019 (SA) score. Two-way repeated-measures ANOVA (seven velocities \u00d7 four conditions) was used. There was no significant difference in SA scores for any of the biomechanical variables for velocity (except contact time and braking phase duration; p = 0.003 and p = 0.002, respectively), condition, or interaction. Mean SA scores varied between \u223c1% and 2% for contact time (1.5 \u00b1 0.8%), flight time (1.6 \u00b1 0.6%), step length (0.8 \u00b1 0.2%), peak vertical force (1.2 \u00b1 0.5%), and mean vertical loading rate (2.1 \u00b1 1.0%). Mean SA scores ranged from \u223c2% to 5% for duration of braking (1.6 \u00b1 0.7%) and push-off phases (1.9 \u00b1 0.6%), as well as peak braking (5.0 \u00b1 1.9%) and push-off forces (4.8 \u00b1 1.7%). In conclusion, the trained runners exhibited relatively even strides, with mechanical asymmetries remaining low-to-moderate across a range of submaximal, constant running velocities (ranging from 8 to 20 km\u00b7h\u22121) and varying levels of hypoxia severity (between normoxia and severe hypoxia).<\/jats:p>","DOI":"10.3390\/sym15071303","type":"journal-article","created":{"date-parts":[[2023,6,26]],"date-time":"2023-06-26T02:05:02Z","timestamp":1687745102000},"page":"1303","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Mechanical Asymmetries during Treadmill Running: Effects of Running Velocity and Hypoxic Exposure"],"prefix":"10.3390","volume":"15","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-0725-0999","authenticated-orcid":false,"given":"Chris Chow Li","family":"Tee","sequence":"first","affiliation":[{"name":"Division of Research and Innovation, National Sports Institute of Malaysia, Kuala Lumpur 57000, Malaysia"},{"name":"Sport and Exercise Medicine Group, Swinburne University of Technology, Melbourne 3122, Australia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2940-0775","authenticated-orcid":false,"given":"Mee Chee","family":"Chong","sequence":"additional","affiliation":[{"name":"Sport and Exercise Medicine Group, Swinburne University of Technology, Melbourne 3122, Australia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2234-718X","authenticated-orcid":false,"given":"Viswanath","family":"Sundar","sequence":"additional","affiliation":[{"name":"Division of Sports Performance, National Sports Institute of Malaysia, Kuala Lumpur 57000, Malaysia"},{"name":"Department of Physical Education and Sports Science, Visva-Bharati University, Santiniketan 731235, India"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Chuen Leang","family":"Chok","sequence":"additional","affiliation":[{"name":"Division of Sports Performance, National Sports Institute of Malaysia, Kuala Lumpur 57000, Malaysia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Wee Kian","family":"Yeo","sequence":"additional","affiliation":[{"name":"Division of Research and Innovation, National Sports Institute of Malaysia, Kuala Lumpur 57000, Malaysia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4797-182X","authenticated-orcid":false,"given":"Olivier","family":"Girard","sequence":"additional","affiliation":[{"name":"School of Human Sciences (Exercise and Sport Science), The University of Western Australia, Perth 6009, Australia"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2023,6,23]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1135","DOI":"10.1080\/02640414.2017.1361894","article-title":"Effects of inter-limb asymmetries on physical and sports performance: A systematic review","volume":"36","author":"Bishop","year":"2018","journal-title":"J. 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