{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,30]],"date-time":"2026-10-30T09:27:55Z","timestamp":1793352475103,"version":"4.5.0"},"reference-count":42,"publisher":"MDPI AG","issue":"22","license":[{"start":{"date-parts":[[2021,11,10]],"date-time":"2021-11-10T00:00:00Z","timestamp":1636502400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>This study\u2019s aim was to analyze muscle activation and kinematics of sled-pushing and resisted-parachute sprinting with three load conditions on an instrumentalized SKILLRUN\u00ae treadmill. Nine male amateur rugby union players (21.3 \u00b1 4.3 years, 75.8 \u00b1 10.2 kg, 176.6 \u00b1 8.8 cm) performed a sled-push session consisting of three 15-m repetitions at 20%, 55% and 90% body mas and another resisted-parachute session using three different parachute sizes (XS, XL and 3XL). Sprinting kinematics and muscle activity of three lower-limb muscles (biceps femoris (BF), vastus lateralis (VL) and gastrocnemius medialis (GM)) were measured. A repeated-measures analysis of variance (RM-ANOVA) showed that higher loads during the sled-push increased (VL) (p \u2264 0.001) and (GM) (p \u2264 0.001) but not (BF) (p = 0.278) activity. Furthermore, it caused significant changes in sprinting kinematics, stiffness and joint angles. Resisted-parachute sprinting did not change kinematics or muscle activation, despite producing a significant overload (i.e., speed loss). In conclusion, increased sled-push loading caused disruptions in sprinting technique and altered lower-limb muscle activation patterns as opposed to the resisted-parachute. These findings might help practitioners determine the more adequate resisted sprint exercise and load according to the training objective (e.g., power production or speed performance).<\/jats:p>","DOI":"10.3390\/s21227482","type":"journal-article","created":{"date-parts":[[2021,11,11]],"date-time":"2021-11-11T23:04:46Z","timestamp":1636671886000},"page":"7482","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":10,"title":["Electromyography, Stiffness and Kinematics of Resisted Sprint Training in the Specialized SKILLRUN\u00ae Treadmill Using Different Load Conditions in Rugby Players"],"prefix":"10.3390","volume":"21","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-3509-3350","authenticated-orcid":false,"given":"Antonio","family":"Mart\u00ednez-Serrano","sequence":"first","affiliation":[{"name":"UCAM Research Center for High Performance Sport, Catholic University of Murcia, 30107 Murcia, Spain"},{"name":"Strength and Conditioning Society, 00118 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Elena","family":"Mar\u00edn-Cascales","sequence":"additional","affiliation":[{"name":"Strength and Conditioning Society, 00118 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5762-4653","authenticated-orcid":false,"given":"Konstantinos","family":"Spyrou","sequence":"additional","affiliation":[{"name":"UCAM Research Center for High Performance Sport, Catholic University of Murcia, 30107 Murcia, Spain"},{"name":"Strength and Conditioning Society, 00118 Rome, Italy"},{"name":"Faculty of Sports Sciences, Catholic University of Murcia, 30107 Murcia, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8571-3189","authenticated-orcid":false,"given":"Tom\u00e1s T.","family":"Freitas","sequence":"additional","affiliation":[{"name":"UCAM Research Center for High Performance Sport, Catholic University of Murcia, 30107 Murcia, Spain"},{"name":"Strength and Conditioning Society, 00118 Rome, Italy"},{"name":"Faculty of Sports Sciences, Catholic University of Murcia, 30107 Murcia, Spain"},{"name":"NAR\u2014Nucleus of High Performance in Sport, S\u00e3o Paulo 04753-060, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9792-6656","authenticated-orcid":false,"given":"Pedro E.","family":"Alcaraz","sequence":"additional","affiliation":[{"name":"UCAM Research Center for High Performance Sport, Catholic University of Murcia, 30107 Murcia, Spain"},{"name":"Strength and Conditioning Society, 00118 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2021,11,10]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"125","DOI":"10.1260\/1747-9541.6.1.125","article-title":"The Development of Position-Specific Performance Indicators in Elite Youth Rugby League: A Coach\u2019s Perspective","volume":"6","author":"Cupples","year":"2011","journal-title":"Int. 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