{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T01:25:13Z","timestamp":1760059513303,"version":"build-2065373602"},"reference-count":42,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2025,6,18]],"date-time":"2025-06-18T00:00:00Z","timestamp":1750204800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"FCT","award":["2023.15325.PEX","9th edition of IDI&CA"],"award-info":[{"award-number":["2023.15325.PEX","9th edition of IDI&CA"]}]},{"name":"IPL\/IDI&amp;CA2024\/CSAT-OBC-ISEL","award":["2023.15325.PEX","9th edition of IDI&CA"],"award-info":[{"award-number":["2023.15325.PEX","9th edition of IDI&CA"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Weightlifting is a common fitness activity and can be practiced individually without supervision. However, performing regular weightlifting exercises without any form of feedback can lead to serious injuries. To counter this, this work proposes a different approach to automatic weightlifting supervision off-the-person. The proposed embedded system is coupled to the weights and evaluates if they follow the correct trajectory in real time. The system is based on a low-power embedded System-on-a-Chip to perform the classification of the correctness of physical exercises using a Convolutional Neural Network with data from the embedded IMU. It is a low-cost solution and can be adapted to the characteristics of specific exercises to fine-tune the performance of the athlete. Experimental results show real-time monitoring capability with an average accuracy close to 95%. To favor its use, the prototypes have been enclosed on a custom 3D case and validated in an operational environment. All research outputs, developments, and engineering models are publicly available.<\/jats:p>","DOI":"10.3390\/s25123808","type":"journal-article","created":{"date-parts":[[2025,6,18]],"date-time":"2025-06-18T09:36:00Z","timestamp":1750239360000},"page":"3808","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Intelligent Sports Weights"],"prefix":"10.3390","volume":"25","author":[{"given":"Olga dos Santos","family":"Duarte","sequence":"first","affiliation":[{"name":"Instituto Superior de Engenharia de Lisboa, Instituto Polit\u00e9cnico de Lisboa, Rua Conselheiro Emidio Navarro, 1, 1959-007 Lisboa, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0009-0002-9651-5043","authenticated-orcid":false,"given":"Gustavo","family":"Jacinto","sequence":"additional","affiliation":[{"name":"Instituto Superior de Engenharia de Lisboa, Instituto Polit\u00e9cnico de Lisboa, Rua Conselheiro Emidio Navarro, 1, 1959-007 Lisboa, Portugal"},{"name":"INESC INOV, 1000-029 Lisboa, Portugal"},{"name":"Instituto Superior T\u00e9cnico, University of Lisbon, Av. 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