{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,5]],"date-time":"2026-03-05T17:56:26Z","timestamp":1772733386981,"version":"3.50.1"},"reference-count":49,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2026,2,9]],"date-time":"2026-02-09T00:00:00Z","timestamp":1770595200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"PRR\u2014Recovery and Resilience Plan under the Next Generation EU from the European Union","award":["C644866475-00000012"],"award-info":[{"award-number":["C644866475-00000012"]}]},{"name":"PhD studentship","award":["2025.02573.BDANA"],"award-info":[{"award-number":["2025.02573.BDANA"]}]},{"name":"FCT\u2014Funda\u00e7\u00e3o para a Ci\u00eancia e a Tecnologia, I.P.","award":["UID 00481\/2025"],"award-info":[{"award-number":["UID 00481\/2025"]}]},{"name":"FCT\u2014Funda\u00e7\u00e3o para a Ci\u00eancia e a Tecnologia, I.P.","award":["UID 00127\/2025"],"award-info":[{"award-number":["UID 00127\/2025"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>The transition from cycling to electric micro-mobility, such as e-scooters, introduces distinct safety risks. While physiological sensing is established for monitoring cyclist exertion, its transferability to high-vibration e-scooter environments remains unclear. This study systematically reviews wearable sensors used to detect stress, fatigue, and exertion in cycling and micro-mobility to identify gaps preventing active safety systems. A PRISMA-guided search of IEEE Xplore, Web of Science, PubMed, Scopus, and ScienceDirect was performed on 2 October 2025 for studies published in 2015\u20132025. From 273 records, 11 publications representing nine unique studies met the inclusion criteria. Laboratory studies (n=4) utilizing deep learning (CNN-LSTM) achieved high exertion prediction accuracy (F1 86.3\u201391.7%) but relied on a single redundant dataset (N=27), lacking independent validation. Field studies (n=7) relied on statistical associations between heart rate variability and environmental stress but lacked real-time predictive capabilities. Notably, evidence for automated physiological safety classification in e-scooters is critically underdeveloped. Current models are overfitted to cycling biomechanics and fail to account for e-scooter constraints, such as whole-body vibration. Future research must shift toward Unsupervised Domain Adaptation (UDA) and noise-resilient edge AI architectures to bridge the technological lag in micro-mobility safety.<\/jats:p>","DOI":"10.3390\/s26041110","type":"journal-article","created":{"date-parts":[[2026,2,9]],"date-time":"2026-02-09T08:15:54Z","timestamp":1770624954000},"page":"1110","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["The Micro-Mobility Sensing Gap: A Systematic Review of Physiological Safety Monitoring from Cycling to E-Scooters"],"prefix":"10.3390","volume":"26","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-0001-1810","authenticated-orcid":false,"given":"Syed Tahir Ali","family":"Shah","sequence":"first","affiliation":[{"name":"TEMA\u2014Centre for Mechanical Technology and Automation, Department of Mechanical Engineering, University of Aveiro, Campus Universit\u00e1rio de Santiago, 3810-193 Aveiro, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0681-9354","authenticated-orcid":false,"given":"J. M.","family":"Fernandes","sequence":"additional","affiliation":[{"name":"IEETA\u2014Department of Electronics, Telecommunications and Informatics, University of Aveiro, Campus Universit\u00e1rio de Santiago, 3810-193 Aveiro, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0417-8167","authenticated-orcid":false,"given":"J. P.","family":"Santos","sequence":"additional","affiliation":[{"name":"TEMA\u2014Centre for Mechanical Technology and Automation, Department of Mechanical Engineering, University of Aveiro, Campus Universit\u00e1rio de Santiago, 3810-193 Aveiro, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1614-1962","authenticated-orcid":false,"given":"G.","family":"Constantinescu","sequence":"additional","affiliation":[{"name":"TEMA\u2014Centre for Mechanical Technology and Automation, Department of Mechanical Engineering, University of Aveiro, Campus Universit\u00e1rio de Santiago, 3810-193 Aveiro, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8342-5116","authenticated-orcid":false,"given":"Ant\u00f3nio B.","family":"Pereira","sequence":"additional","affiliation":[{"name":"TEMA\u2014Centre for Mechanical Technology and Automation, Department of Mechanical Engineering, University of Aveiro, Campus Universit\u00e1rio de Santiago, 3810-193 Aveiro, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2026,2,9]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"45","DOI":"10.1080\/01441647.2015.1057877","article-title":"Cycling as a part of daily life: A review of health perspectives","volume":"36","author":"Garrard","year":"2016","journal-title":"Transp. 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