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Physiol."],"abstract":"<jats:sec><jats:title>Background<\/jats:title><jats:p>Power-oriented resistance training (PRT) is one of the most effective exercise programs to counteract neuromuscular and physical function age-related declines. However, the optimal load that maximizes these outcomes or the load-specific adaptations induced on muscle power determinants remain to be better understood. Furthermore, to investigate whether these adaptations are potentially transferred to an untrained limb (i.e., cross-education phenomenon) could be especially relevant during limb-immobilization frequently observed in older people (e.g., after hip fracture).<\/jats:p><\/jats:sec><jats:sec><jats:title>Methods<\/jats:title><jats:p>At least 30 well-functioning older participants (&amp;gt;65 years) will participate in a within-person randomized controlled trial. After an 8-week control period, the effects of two 12-week PRT programs using light vs. heavy loads will be compared using an unilateral exercise model through three study arms (light-load PRT vs. non-exercise; heavy-load PRT vs. non-exercise; and light- vs. heavy- load PRT). Muscle-tendon function, muscle excitation and morphology and physical function will be evaluated to analyze the load-specific effects of PRT in older people. Additionally, the effects of PRT will be examined on a non-exercised contralateral limb.<\/jats:p><\/jats:sec><jats:sec><jats:title>Discussion<\/jats:title><jats:p>Tailored exercise programs are largely demanded given their potentially greater efficiency preventing age-related negative consequences, especially during limb-immobilization. This trial will provide evidence supporting the use of light- or heavy-load PRT on older adults depending on individual needs, improving decision making and exercise program efficacy.<\/jats:p><\/jats:sec><jats:sec><jats:title>Clinical Trial Registration<\/jats:title><jats:p>NCT03724461 registration data: October 30, 2018.<\/jats:p><\/jats:sec>","DOI":"10.3389\/fphys.2021.635094","type":"journal-article","created":{"date-parts":[[2021,2,20]],"date-time":"2021-02-20T16:08:09Z","timestamp":1613837289000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":9,"title":["Effects of Power-Oriented Resistance Training With Heavy vs. Light Loads on Muscle-Tendon Function in Older Adults: A Study Protocol for a Randomized Controlled Trial"],"prefix":"10.3389","volume":"12","author":[{"given":"Carlos","family":"Rodriguez-Lopez","sequence":"first","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Julian","family":"Alcazar","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jose","family":"Losa-Reyna","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Noelia Maria","family":"Martin-Espinosa","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ivan","family":"Baltasar-Fernandez","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ignacio","family":"Ara","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Robert","family":"Csapo","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Luis M.","family":"Alegre","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1965","published-online":{"date-parts":[[2021,2,18]]},"reference":[{"key":"B1","doi-asserted-by":"publisher","first-page":"1369","DOI":"10.1093\/gerona\/glaa013","article-title":"Age- and sex-specific changes in lower-Limb muscle power throughout the lifespan.","volume":"75","author":"Alcazar","year":"2020","journal-title":"J. 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