The effect of a vegan diet with or without resistance exercise on thigh muscle volume in older adults. Research protocol of the Vold-study: a 12-week randomized controlled trial

The effect of a vegan diet with or without resistance exercise on thigh muscle volume in older adults. Research protocol of the Vold-study: a 12-week randomized controlled trial | 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 Study protocol The effect of a vegan diet with or without resistance exercise on thigh muscle volume in older adults. Research protocol of the Vold-study: a 12-week randomized controlled trial Jacintha Domić, Pol Grootswagers, Philippe JM Pinckaers, Inge Groenendijk, and 3 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-4072323/v2 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 26 Dec, 2025 Read the published version in BMC Geriatrics → Version 2 posted 6 You are reading this latest preprint version Show more versions Abstract Background Plant-based diets are increasingly adopted. Plant-based foods exhibit a lower protein quantity and quality compared to animal-based foods. As such, a fully plant-based, i.e. vegan, diet may be suboptimal for the maintenance of skeletal muscle mass later in life. The primary objectives of this study protocol are therefore: 1) To assess the effect of a 12-week self-composed vegan diet in comparison to an omnivorous diet on thigh muscle volume in community-dwelling older adults; and 2) To assess the effect of a 12-week vegan diet combined with twice-weekly resistance exercise (RE) on thigh muscle volume in comparison to a vegan diet without RE in community-dwelling older adults. Methods Seventy-two community-dwelling individuals aged ≥ 65 years with a BMI between 23–32 kg/m 2 will be included in this randomized controlled trial. Eligible participants will be randomly allocated to either follow their habitual omnivorous diet, a self-composed vegan diet, or a self-composed vegan diet combined with two sessions of RE per week for 12 weeks. Participants will be guided through monthly nutrition information meetings. Dietary intake and physical activity levels will be assessed using food records and accelerometery. The primary study outcome will be thigh muscle volume, assessed at baseline and after 12 weeks using magnetic resonance imaging (MRI). Secondary outcomes will be: body composition, muscle fat infiltration, muscle strength, bone mineral density, bone turnover markers, metabolic profile, insulin levels, cobalamin, iron and vitamin D status, hs-CRP, gut metabolomics and metagenomics, gastro-intestinal symptoms and dietary intake. Measurements will take place at baseline, after 6 weeks, and after 12 weeks. Additionally, mixed muscle protein synthesis rates will be assessed during the first ten days of the intervention using a deuterium oxide protocol. Data will be analysed using independent t-tests and linear mixed models. Discussion The results will provide valuable insights regarding the implications of consuming a vegan diet later in life for skeletal muscle and other health outcomes, and may contribute to the substantiation of the envisaged more plant-based dietary guidelines. Trial registration: The trial is registered at clinicaltrials.gov (NCT05809466; registered on 22 February 2023). plant-based food animal-based food skeletal muscle muscle mass aging sustainable food Full Text Additional Declarations Competing interest reported. JD, PJMP, IG and JR declare that they have no competing interests. LJCvL has received research grants, consulting fees, speaking honoraria, or a combination of these for research on the impact of exercise and nutrition on muscle metabolism, which include funding from companies that produce dairy, meat, and/or plant-derived proteins. A full overview on research funding is provided at: https://www.maastrichtuniversity.nl/l.vanloon . LCPGMdG and PG have received grants for research on the impact of nutrition (and exercise) on muscle metabolism, from the Dutch government (ZonMw), the European Union (H2020), and Top Institute Food and Nutrition, which pre-competitively includes funding from food industry (small and medium sized enterprises and larger enterprises). None of these organizations affected the design of the Vold-study. Supplementary Files Additionalfile1.pdf Cite Share Download PDF Status: Published Journal Publication published 26 Dec, 2025 Read the published version in BMC Geriatrics → Version 2 posted Editorial decision: Accepted 28 Oct, 2025 Reviews received at journal 28 Aug, 2025 Reviewers agreed at journal 21 Aug, 2025 Reviewers invited by journal 11 Aug, 2025 Submission checks completed at journal 11 Aug, 2025 First submitted to journal 06 Aug, 2025 You are reading this latest preprint version Show more versions 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. 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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-4072323","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Study protocol","associatedPublications":[],"authors":[{"id":523382798,"identity":"ae034ce5-9ec5-11f0-907b-06cc9d20a69f","order_by":0,"name":"Jacintha 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JD, PJMP, IG and JR declare that they have no competing interests.\nLJCvL has received research grants, consulting fees, speaking honoraria, or a combination of these for research on the impact of exercise and nutrition on muscle metabolism, which\ninclude funding from companies that produce dairy, meat, and/or plant-derived proteins. A full overview on research funding is provided at: https://www.maastrichtuniversity.nl/l.vanloon.\nLCPGMdG and PG have received grants for research on the impact of nutrition (and exercise) on muscle metabolism, from the Dutch government (ZonMw), the European Union (H2020), and Top Institute Food and Nutrition, which pre-competitively includes funding from food industry (small and medium sized enterprises and larger enterprises). \nNone of these organizations affected the design of the Vold-study.","formattedTitle":"The effect of a vegan diet with or without resistance exercise on thigh muscle volume in older adults. Research protocol of the Vold-study: a 12-week randomized controlled trial","fulltext":[],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":false,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":true,"isAuthorSuppliedPdf":true,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":true,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"bmc-geriatrics","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"bgtc","sideBox":"Learn more about [BMC Geriatrics](http://bmcgeriatr.biomedcentral.com/)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/bgtc/default.aspx","title":"BMC Geriatrics","twitterHandle":"BMC_series","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"em","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"plant-based food, animal-based food, skeletal muscle, muscle mass, aging, sustainable food","lastPublishedDoi":"10.21203/rs.3.rs-4072323/v2","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-4072323/v2","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003ch2\u003eBackground\u003c/h2\u003e\u003cp\u003ePlant-based diets are increasingly adopted. Plant-based foods exhibit a lower protein quantity and quality compared to animal-based foods. As such, a fully plant-based, i.e. vegan, diet may be suboptimal for the maintenance of skeletal muscle mass later in life. The primary objectives of this study protocol are therefore: 1) To assess the effect of a 12-week self-composed vegan diet in comparison to an omnivorous diet on thigh muscle volume in community-dwelling older adults; and 2) To assess the effect of a 12-week vegan diet combined with twice-weekly resistance exercise (RE) on thigh muscle volume in comparison to a vegan diet without RE in community-dwelling older adults.\u003c/p\u003e\u003ch2\u003eMethods\u003c/h2\u003e\u003cp\u003eSeventy-two community-dwelling individuals aged\u0026thinsp;\u0026ge;\u0026thinsp;65 years with a BMI between 23\u0026ndash;32 kg/m\u003csup\u003e2\u003c/sup\u003e will be included in this randomized controlled trial. Eligible participants will be randomly allocated to either follow their habitual omnivorous diet, a self-composed vegan diet, or a self-composed vegan diet combined with two sessions of RE per week for 12 weeks. Participants will be guided through monthly nutrition information meetings. Dietary intake and physical activity levels will be assessed using food records and accelerometery. The primary study outcome will be thigh muscle volume, assessed at baseline and after 12 weeks using magnetic resonance imaging (MRI). Secondary outcomes will be: body composition, muscle fat infiltration, muscle strength, bone mineral density, bone turnover markers, metabolic profile, insulin levels, cobalamin, iron and vitamin D status, hs-CRP, gut metabolomics and metagenomics, gastro-intestinal symptoms and dietary intake. Measurements will take place at baseline, after 6 weeks, and after 12 weeks. Additionally, mixed muscle protein synthesis rates will be assessed during the first ten days of the intervention using a deuterium oxide protocol. Data will be analysed using independent t-tests and linear mixed models.\u003c/p\u003e\u003ch2\u003eDiscussion\u003c/h2\u003e\u003cp\u003e The results will provide valuable insights regarding the implications of consuming a vegan diet later in life for skeletal muscle and other health outcomes, and may contribute to the substantiation of the envisaged more plant-based dietary guidelines.\u003c/p\u003e\u003ch2\u003eTrial registration:\u003c/h2\u003e\u003cp\u003eThe trial is registered at clinicaltrials.gov (NCT05809466; registered on 22 February 2023).\u003c/p\u003e","manuscriptTitle":"The effect of a vegan diet with or without resistance exercise on thigh muscle volume in older adults. 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