{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,23]],"date-time":"2026-01-23T08:14:27Z","timestamp":1769156067818,"version":"3.49.0"},"reference-count":35,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2014,2,18]],"date-time":"2014-02-18T00:00:00Z","timestamp":1392681600000},"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>Accelerometer-based activity monitors are popular for monitoring physical activity. In this study, we investigated optimal sensor placement for increasing the quality of studies that utilize accelerometer data to assess physical activity. We performed a  two-staged study, focused on sensor location and type of mounting. Ten subjects walked at various walking speeds on a treadmill, performed a deskwork protocol, and walked on level ground, while simultaneously wearing five ProMove2 sensors with a snug fit  on an elastic waist belt. We found that sensor location, type of activity, and their interaction-effect affected sensor output. The most lateral positions on the waist belt were the least sensitive for interference. The effect of mounting was explored, by making two subjects repeat the experimental protocol with sensors more loosely fitted to the elastic belt. The loose fit resulted in lower sensor output, except for the deskwork protocol, where output was higher. In order to increase the reliability and to reduce the variability of sensor output, researchers should place activity sensors on the most lateral position of a participant\u2019s waist belt. If the sensor hampers free movement, it may be positioned slightly more forward on the belt. Finally, sensors should be fitted tightly to the body.<\/jats:p>","DOI":"10.3390\/s140203188","type":"journal-article","created":{"date-parts":[[2014,2,18]],"date-time":"2014-02-18T11:07:10Z","timestamp":1392721630000},"page":"3188-3206","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":55,"title":["Optimal Sensor Placement for Measuring Physical Activity with a 3D Accelerometer"],"prefix":"10.3390","volume":"14","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-4760-3007","authenticated-orcid":false,"given":"Simone","family":"Boerema","sequence":"first","affiliation":[{"name":"Telemedicine Group, Roessingh Research and Development, P.O. Box 310, 7500 AH, Enschede, The Netherlands"},{"name":"Telemedicine Group, Faculty of Electrical Engineering, Mathematics and Computer Science, University of Twente, P.O. Box 217, 7500 AE, Enschede, The Netherlands"}]},{"given":"Lex","family":"Van Velsen","sequence":"additional","affiliation":[{"name":"Telemedicine Group, Roessingh Research and Development, P.O. Box 310, 7500 AH, Enschede, The Netherlands"},{"name":"Telemedicine Group, Faculty of Electrical Engineering, Mathematics and Computer Science, University of Twente, P.O. Box 217, 7500 AE, Enschede, The Netherlands"}]},{"given":"Leendert","family":"Schaake","sequence":"additional","affiliation":[{"name":"Telemedicine Group, Roessingh Research and Development, P.O. Box 310, 7500 AH, Enschede, The Netherlands"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9563-6420","authenticated-orcid":false,"given":"Thijs","family":"T\u00f6nis","sequence":"additional","affiliation":[{"name":"Telemedicine Group, Roessingh Research and Development, P.O. Box 310, 7500 AH, Enschede, The Netherlands"},{"name":"Telemedicine Group, Faculty of Electrical Engineering, Mathematics and Computer Science, University of Twente, P.O. Box 217, 7500 AE, Enschede, The Netherlands"}]},{"given":"Hermie","family":"Hermens","sequence":"additional","affiliation":[{"name":"Telemedicine Group, Roessingh Research and Development, P.O. Box 310, 7500 AH, Enschede, The Netherlands"},{"name":"Telemedicine Group, Faculty of Electrical Engineering, Mathematics and Computer Science, University of Twente, P.O. Box 217, 7500 AE, Enschede, The Netherlands"}]}],"member":"1968","published-online":{"date-parts":[[2014,2,18]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"7772","DOI":"10.3390\/s100807772","article-title":"A review of accelerometry-based wearable motion detectors for physical activity monitoring","volume":"10","author":"Yang","year":"2010","journal-title":"Sensors"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"S195","DOI":"10.1139\/H07-107","article-title":"Physical activity and inactivity profiling: The next generation","volume":"32","author":"Esliger","year":"2007","journal-title":"Appl. Physiol. Nutr. Metab."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"S13","DOI":"10.1249\/MSS.0b013e3182399bc8","article-title":"Redefining the roles of sensors in objective physical activity monitoring","volume":"44","author":"Chen","year":"2012","journal-title":"Med. Sci. 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