{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,20]],"date-time":"2026-03-20T21:41:26Z","timestamp":1774042886657,"version":"3.50.1"},"reference-count":46,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2013,8,2]],"date-time":"2013-08-02T00:00:00Z","timestamp":1375401600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/3.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>In alpine ski racing the relationships between skier kinetics and kinematics and their effect on performance and injury-related aspects are not well understood. There is currently no validated system to determine all external forces simultaneously acting on skiers, particularly under race conditions and throughout entire races. To address the problem, this study proposes and assesses a method for determining skier kinetics with a single lightweight differential global navigation satellite system (dGNSS). The dGNSS kinetic method was compared to a reference system for six skiers and two turns each. The pattern differences obtained between the measurement systems (offset \u00b1 SD) were  \u221226 \u00b1 152 N for the ground reaction force, 1 \u00b1 96 N for ski friction and \u22126 \u00b1 6 N for the air drag force. The differences between turn means were small. The error pattern within the dGNSS kinetic method was highly repeatable and precision was therefore good (SD within system: 63 N ground reaction force, 42 N friction force and 7 N air drag force) allowing instantaneous relative comparisons and identification of discriminative meaningful changes. The method is therefore highly valid in assessing relative differences between skiers in the same turn, as well as turn means between different turns. The system is suitable to measure large capture volumes under race conditions.<\/jats:p>","DOI":"10.3390\/s130809821","type":"journal-article","created":{"date-parts":[[2013,8,2]],"date-time":"2013-08-02T11:56:22Z","timestamp":1375444582000},"page":"9821-9835","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":78,"title":["Determination of External Forces in Alpine Skiing Using a Differential Global Navigation Satellite System"],"prefix":"10.3390","volume":"13","author":[{"given":"Matthias","family":"Gilgien","sequence":"first","affiliation":[{"name":"Department of Physical Performance, Norwegian School of Sport Sciences, Sognsveien 220,  Oslo 0806, Norway"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0353-1021","authenticated-orcid":false,"given":"J\u00f6rg","family":"Sp\u00f6rri","sequence":"additional","affiliation":[{"name":"Department of Sport Science and Kinesiology, University of Salzburg, Schlossallee 49,  Hallein\/Rif 5400, Austria"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Julien","family":"Chardonnens","sequence":"additional","affiliation":[{"name":"Laboratory of Movement Analysis and Measurement, Ecole Polytechnique F\u00e9d\u00e9rale de Lausanne, Station 11, Lausanne 1015, Switzerland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Josef","family":"Kr\u00f6ll","sequence":"additional","affiliation":[{"name":"Department of Sport Science and Kinesiology, University of Salzburg, Schlossallee 49,  Hallein\/Rif 5400, Austria"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3857-2584","authenticated-orcid":false,"given":"Erich","family":"M\u00fcller","sequence":"additional","affiliation":[{"name":"Department of Sport Science and Kinesiology, University of Salzburg, Schlossallee 49,  Hallein\/Rif 5400, Austria"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2013,8,2]]},"reference":[{"key":"ref_1","first-page":"269","article-title":"Calculation of Friction and Reaction Forces during an Alpine World Cup Downhill Race","volume":"Volume 1","author":"Moritz","year":"2006","journal-title":"The Engineering of Sport"},{"key":"ref_2","unstructured":"Reid, R. 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