{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T01:51:11Z","timestamp":1760147471378,"version":"build-2065373602"},"reference-count":40,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2023,2,4]],"date-time":"2023-02-04T00:00:00Z","timestamp":1675468800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"German Federal Ministry of Education and Research","award":["16DHB4014"],"award-info":[{"award-number":["16DHB4014"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Running power is a popular measure to gauge objective intensity. It has recently been shown, though, that foot-worn sensors alone cannot reflect variations in the exerted energy that stems from changes in the running economy. In order to support long-term improvement in running, these changes need to be taken into account. We propose leveraging the presence of two additional sensors worn by the most ambitious recreational runners for improved measurement: a watch and a heart rate chest strap. Using these accelerometers, which are already present and distributed over the athlete\u2019s body, carries more information about metabolic demand than a single foot-worn sensor. In this work, we demonstrate the mutual information between acceleration data and the metabolic demand of running by leveraging the information bottleneck of a constrained convolutional neural network. We perform lab measurements on 29 ambitious recreational runners (age = 28 \u00b1 7 years, weekly running distance = 50 \u00b1 25 km, V\u02d9O2max = 60.3 \u00b1 7.4 mL \u00b7 min\u22121\u00b7kg\u22121). We show that information about the metabolic demand of running is contained in kinetic data. Additionally, we prove that the combination of three sensors (foot, torso, and lower arm) carries significantly more information than a single foot-worn sensor. We advocate for the development of running power systems that incorporate the sensors in watches and chest straps to improve the validity of running power and, thereby, long-term training planning.<\/jats:p>","DOI":"10.3390\/s23041756","type":"journal-article","created":{"date-parts":[[2023,2,6]],"date-time":"2023-02-06T02:06:43Z","timestamp":1675649203000},"page":"1756","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Revealing the Mutual Information between Body-Worn Sensors and Metabolic Cost in Running"],"prefix":"10.3390","volume":"23","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-1194-3429","authenticated-orcid":false,"given":"Tobias","family":"Baumgartner","sequence":"first","affiliation":[{"name":"Institute of Exercise Training and Sport Informatics, Department of Cognitive and Team\/Racket Sport Research, German Sport University Cologne, 50933 Cologne, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2477-8699","authenticated-orcid":false,"given":"Stefanie","family":"Klatt","sequence":"additional","affiliation":[{"name":"Institute of Exercise Training and Sport Informatics, Department of Cognitive and Team\/Racket Sport Research, German Sport University Cologne, 50933 Cologne, Germany"},{"name":"School of Sport and Health Sciences, University of Brighton, Eastbourne BN20 7SR, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Lars","family":"Donath","sequence":"additional","affiliation":[{"name":"Department of Intervention Research in Exercise Training, German Sport University Cologne, 50933 Cologne, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2023,2,4]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"694","DOI":"10.1177\/1747954119872321","article-title":"Three Norwegian brothers all European 1500 m champions: What is the secret?","volume":"14","author":"Tjelta","year":"2019","journal-title":"Int. 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