Probing Gait Adaptations: The Impact of Aging on Dynamic Stability and Reflex Control Under Varied Weight-Bearing Conditions

Probing Gait Adaptations: The Impact of Aging on Dynamic Stability and Reflex Control Under Varied Weight-Bearing Conditions | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Probing Gait Adaptations: The Impact of Aging on Dynamic Stability and Reflex Control Under Varied Weight-Bearing Conditions Michelle Gwerder, Ursina Camenzind, Samira Wild, Yong K. Kim, and 2 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-6647283/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 30 Jun, 2025 Read the published version in European Journal of Applied Physiology → Version 1 posted You are reading this latest preprint version Abstract Maintaining stable walking patterns is essential for preserving health and well-being throughout the aging process. While several biomechanical models have been developed to describe adaptation and walking stability, the role of reflex control remains underexplored. This study aimed to understand the mechanisms by which disturbances to gait patterns (changes to weight-bearing conditions) are influencing gait adaptations, gait variability, and their underlying reflex control during treadmill walking in young and older adults. Twenty young (mean age 25.7±3.3 years) and 20 older adults (62.3±4.3 years) walked on a treadmill under five weight-bearing conditions: normal bodyweight, 20% and 40% additional weight (bodyweight loading), and 20% and 40% reduced weight (bodyweight unloading). Linear mixed-effects models were used to assess spatiotemporal gait parameters, margin of stability, gait variability (standard deviation), and H-reflex responses during stance phase. Bodyweight unloading significantly reduced antero-posterior margin of stability (p<0.01). Compared to young adults, older adults exhibited shorter stride length, longer double-limb support time, larger antero-posterior margin of stability, and increased variability (p<0.05). While H-reflex amplitudes increased with increasing weight-bearing in young adults, older adults were less capable to modulate their H-reflex amplitude across weight conditions. These findings suggest that gait adaptations under altered weight-bearing conditions involve shifts in temporal regulation and movement strategies. The reduced reflex modulation in older adults may indicate a limited ability to adapt spinal-level reflex responses, leading to greater reliance on other balance control mechanisms. Understanding these neuromuscular adaptations is essential for designing prevention programs to enhance stability and prevent falls. Aging dynamic stability gait adaptation gait variability reflex control Full Text Additional Declarations The authors declare no competing interests. Supplementary Files SupplementaryMaterial.pdf Cite Share Download PDF Status: Published Journal Publication published 30 Jun, 2025 Read the published version in European Journal of Applied Physiology → Version 1 posted You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-6647283","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":455411512,"identity":"d6af4b59-c55a-4c9e-92cf-e2c534178e0e","order_by":0,"name":"Michelle Gwerder","email":"data:image/png;base64,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","orcid":"https://orcid.org/0000-0003-4484-9244","institution":"ETH Zurich","correspondingAuthor":true,"prefix":"","firstName":"Michelle","middleName":"","lastName":"Gwerder","suffix":""},{"id":455411513,"identity":"b7386a8a-46cd-42be-82d1-ed665fd9f648","order_by":1,"name":"Ursina Camenzind","email":"","orcid":"","institution":"ETH Zurich","correspondingAuthor":false,"prefix":"","firstName":"Ursina","middleName":"","lastName":"Camenzind","suffix":""},{"id":455411514,"identity":"d69a2723-961f-4090-b504-c04a34c228e0","order_by":2,"name":"Samira Wild","email":"","orcid":"","institution":"ETH Zurich","correspondingAuthor":false,"prefix":"","firstName":"Samira","middleName":"","lastName":"Wild","suffix":""},{"id":455411515,"identity":"99135bec-6332-4e1f-af02-454208334728","order_by":3,"name":"Yong K. 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While several biomechanical models have been developed to describe adaptation and walking stability, the role of reflex control remains underexplored. This study aimed to understand the mechanisms by which disturbances to gait patterns (changes to weight-bearing conditions) are influencing gait adaptations, gait variability, and their underlying reflex control during treadmill walking in young and older adults.\u003c/p\u003e\n\u003cp\u003eTwenty young (mean age 25.7±3.3 years) and 20 older adults (62.3±4.3 years) walked on a treadmill under five weight-bearing conditions: normal bodyweight, 20% and 40% additional weight (bodyweight loading), and 20% and 40% reduced weight (bodyweight unloading). Linear mixed-effects models were used to assess spatiotemporal gait parameters, margin of stability, gait variability (standard deviation), and H-reflex responses during stance phase.\u003c/p\u003e\n\u003cp\u003eBodyweight unloading significantly reduced antero-posterior margin of stability (p\u0026lt;0.01). Compared to young adults, older adults exhibited shorter stride length, longer double-limb support time, larger antero-posterior margin of stability, and increased variability (p\u0026lt;0.05). While H-reflex amplitudes increased with increasing weight-bearing in young adults, older adults were less capable to modulate their H-reflex amplitude across weight conditions.\u003c/p\u003e\n\u003cp\u003eThese findings suggest that gait adaptations under altered weight-bearing conditions involve shifts in temporal regulation and movement strategies. The reduced reflex modulation in older adults may indicate a limited ability to adapt spinal-level reflex responses, leading to greater reliance on other balance control mechanisms. Understanding these neuromuscular adaptations is essential for designing prevention programs to enhance stability and prevent falls.\u003c/p\u003e","manuscriptTitle":"Probing Gait Adaptations: The Impact of Aging on Dynamic Stability and Reflex Control Under Varied Weight-Bearing Conditions","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-05-14 02:13:06","doi":"10.21203/rs.3.rs-6647283/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"2db65de6-bf64-4489-8bb7-61797e14d854","owner":[],"postedDate":"May 14th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"published-in-journal","subjectAreas":[],"tags":[],"updatedAt":"2025-12-15T23:24:37+00:00","versionOfRecord":{"articleIdentity":"rs-6647283","link":"https://doi.org/10.1007/s00421-025-05884-1","journal":{"identity":"european-journal-of-applied-physiology","isVorOnly":false,"title":"European Journal of Applied Physiology"},"publishedOn":"2025-07-01 00:00:00","publishedOnDateReadable":"July 1st, 2025"},"versionCreatedAt":"2025-05-14 02:13:06","video":"","vorDoi":"10.1007/s00421-025-05884-1","vorDoiUrl":"https://doi.org/10.1007/s00421-025-05884-1","workflowStages":[]},"version":"v1","identity":"rs-6647283","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-6647283","identity":"rs-6647283","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}