{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T01:26:15Z","timestamp":1760145975929,"version":"build-2065373602"},"reference-count":21,"publisher":"MDPI AG","issue":"18","license":[{"start":{"date-parts":[[2024,9,17]],"date-time":"2024-09-17T00:00:00Z","timestamp":1726531200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Electronics"],"abstract":"<jats:p>One of the significant advantages of technological evolution is the greater ease of collecting and analyzing data. Miniaturization, wireless communication protocols and IoT allow the use of sensors to collect data, with all the potential to support decision making in real time. In this paper, we describe the design and implementation of a digital solution to guide the intensity of training or physical activity, based on heart rate wearable sensors applied to participants in group sessions. Our system, featuring a unified engine that simplifies sensor management and minimizes user disruption, has been proven effective for real-time monitoring. It includes custom alerts during variable-intensity workouts, and ensures data preservation for subsequent analysis by physiologists or clinicians. This solution has been used in sessions of up to six participants and sensors up to 12 m away from the gateway device. We describe some challenges and constraints we face in collecting data from multiple and possibly different sensors simultaneously via Bluetooth Low Energy, and the approaches we follow to overcome them. We conduct an in-depth questionnaire to identify potential obstacles and drivers for system acceptance. We also discuss some possibilities for extension and improvement of our system.<\/jats:p>","DOI":"10.3390\/electronics13183687","type":"journal-article","created":{"date-parts":[[2024,9,18]],"date-time":"2024-09-18T01:16:10Z","timestamp":1726622170000},"page":"3687","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Sensor-Based Real-Time Monitoring Approach for Multi-Participant Workout Intensity Management"],"prefix":"10.3390","volume":"13","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-3025-0687","authenticated-orcid":false,"given":"Jos\u00e9","family":"Saias","sequence":"first","affiliation":[{"name":"Departamento de Inform\u00e1tica, Escola de Ci\u00eancias e Tecnologia, Universidade de \u00c9vora, Rua Rom\u00e3o Ramalho, 59, 7000-671 \u00c9vora, Portugal"},{"name":"VISTA Lab, ALGORITMI Research Centre, University of \u00c9vora, 7000-671 \u00c9vora, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9009-5693","authenticated-orcid":false,"given":"Jorge","family":"Bravo","sequence":"additional","affiliation":[{"name":"Departamento de Desporto e Sa\u00fade, Escola de Sa\u00fade e Desenvolvimento Humano, Universidade de \u00c9vora, 7000-671 \u00c9vora, Portugal"},{"name":"Comprehensive Health Research Centre, University of \u00c9vora, Largo Marqu\u00eas de Marialva, Apart. 94, 7002-554 \u00c9vora, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2024,9,17]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"919","DOI":"10.1007\/s11390-011-1189-5","article-title":"Internet of Things: Objectives and Scientific Challenges","volume":"26","author":"Ma","year":"2011","journal-title":"J. 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Available online: https:\/\/www.everythingrf.com\/community\/going-the-distance-four-approaches-for-expanding-the-range-of-bluetooth."}],"container-title":["Electronics"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2079-9292\/13\/18\/3687\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T15:57:53Z","timestamp":1760111873000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2079-9292\/13\/18\/3687"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2024,9,17]]},"references-count":21,"journal-issue":{"issue":"18","published-online":{"date-parts":[[2024,9]]}},"alternative-id":["electronics13183687"],"URL":"https:\/\/doi.org\/10.3390\/electronics13183687","relation":{},"ISSN":["2079-9292"],"issn-type":[{"type":"electronic","value":"2079-9292"}],"subject":[],"published":{"date-parts":[[2024,9,17]]}}}