{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,11]],"date-time":"2026-07-11T11:37:20Z","timestamp":1783769840193,"version":"3.55.0"},"reference-count":33,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2023,1,4]],"date-time":"2023-01-04T00:00:00Z","timestamp":1672790400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"CIHR Post-Doctoral Fellowship Award","award":["#181747"],"award-info":[{"award-number":["#181747"]}]},{"name":"Dalhousie University Department of Medicine University Internal Medicine Research Foundation Research Fellowship Award","award":["#181747"],"award-info":[{"award-number":["#181747"]}]},{"name":"Killam predoctoral scholarship and a Nova Scotia Graduate Scholarship","award":["#181747"],"award-info":[{"award-number":["#181747"]}]},{"name":"Nova Scotia Graduate Scholarship and a Fredrick Banting and Charles Best CIHR Master\u2019s Award","award":["#181747"],"award-info":[{"award-number":["#181747"]}]},{"name":"Heart &amp; Stroke BrightRed Scholarship","award":["#181747"],"award-info":[{"award-number":["#181747"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Objective monitors such as the activPAL characterize time when the thigh is horizontal as sedentary time. However, there are physiological differences between lying, bent-legged sitting, and straight-legged sitting. We introduce a three-monitor configuration to assess detailed sedentary postures and demonstrate its use in characterizing such positions in free-living conditions. We explored time spent in each sedentary posture between prolonged (&gt;1 h) versus non-prolonged (&lt;1 h) sedentary bouts. In total, 35 healthy adults (16\u2640, 24 \u00b1 3 years; 24 h\/day for 6.8 \u00b1 1.0 days) wore an activPAL accelerometer on their thigh, torso, and shin. Hip and knee joint flexion angle estimates were determined during sedentary bouts using the dot-product method between the torso\u2013thigh and thigh\u2013shin, respectively. Compared to lying (69 \u00b1 60 min\/day) or straight-legged sitting (113 \u00b1 100 min\/day), most time was spent in bent-legged sitting (439 \u00b1 101 min\/day, p &lt; 0.001). Most of the bent-legged sitting time was accumulated in non-prolonged bouts (328 \u00b1 83 vs. 112 \u00b1 63 min\/day, p &lt; 0.001). In contrast, similar time was spent in straight-legged sitting and lying between prolonged\/non-prolonged bouts (both, p &gt; 0.26). We document that a considerable amount of waking time is accumulated in lying or straight-legged sitting. This methodological approach equips researchers with a means of characterizing detailed sedentary postures in uncontrolled conditions and may help answer novel research questions on sedentariness.<\/jats:p>","DOI":"10.3390\/s23020587","type":"journal-article","created":{"date-parts":[[2023,1,5]],"date-time":"2023-01-05T02:28:53Z","timestamp":1672885733000},"page":"587","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":10,"title":["Characterization of Detailed Sedentary Postures Using a Tri-Monitor ActivPAL Configuration in Free-Living Conditions"],"prefix":"10.3390","volume":"23","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-0665-5062","authenticated-orcid":false,"given":"Myles W.","family":"O\u2019Brien","sequence":"first","affiliation":[{"name":"School of Physiotherapy (Faculty of Health) & Division of Geriatric Medicine (Faculty of Medicine), Dalhousie University, Halifax, NS B3H 4R2, Canada"},{"name":"Geriatric Medicine Research, Dalhousie University & Nova Scotia Health, Halifax, NS B3H 4R2, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1632-200X","authenticated-orcid":false,"given":"W. Seth","family":"Daley","sequence":"additional","affiliation":[{"name":"Division of Kinesiology, School of Health and Human Performance, Faculty of Health, Dalhousie University, Halifax, NS B3H 4R2, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Beverly D.","family":"Schwartz","sequence":"additional","affiliation":[{"name":"Division of Kinesiology, School of Health and Human Performance, Faculty of Health, Dalhousie University, Halifax, NS B3H 4R2, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Madeline E.","family":"Shivgulam","sequence":"additional","affiliation":[{"name":"Division of Kinesiology, School of Health and Human Performance, Faculty of Health, Dalhousie University, Halifax, NS B3H 4R2, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8634-3765","authenticated-orcid":false,"given":"Yanlin","family":"Wu","sequence":"additional","affiliation":[{"name":"Division of Kinesiology, School of Health and Human Performance, Faculty of Health, Dalhousie University, Halifax, NS B3H 4R2, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3462-8037","authenticated-orcid":false,"given":"Derek S.","family":"Kimmerly","sequence":"additional","affiliation":[{"name":"Division of Kinesiology, School of Health and Human Performance, Faculty of Health, Dalhousie University, Halifax, NS B3H 4R2, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ryan J.","family":"Frayne","sequence":"additional","affiliation":[{"name":"Division of Kinesiology, School of Health and Human Performance, Faculty of Health, Dalhousie University, Halifax, NS B3H 4R2, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2023,1,4]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"75","DOI":"10.1186\/s12966-017-0525-8","article-title":"Sedentary Behavior Research Network (SBRN)\u2014Terminology Consensus Project Process and Outcome","volume":"14","author":"Tremblay","year":"2017","journal-title":"Int. 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