{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,29]],"date-time":"2026-10-29T04:19:04Z","timestamp":1793247544132,"version":"4.5.0"},"reference-count":55,"publisher":"Public Library of Science (PLoS)","issue":"2","license":[{"start":{"date-parts":[[2025,2,10]],"date-time":"2025-02-10T00:00:00Z","timestamp":1739145600000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001804","name":"Canada Research Chairs","doi-asserted-by":"publisher","id":[{"id":"10.13039\/501100001804","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100000245","name":"Michael Smith Health Research BC","doi-asserted-by":"publisher","id":[{"id":"10.13039\/501100000245","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Canadian Institutes of Health Research Foundation Grant","award":["143340"],"award-info":[{"award-number":["143340"]}]}],"content-domain":{"domain":["www.plosone.org"],"crossmark-restriction":false},"short-container-title":["PLoS ONE"],"abstract":"<jats:sec id=\"sec001\">\n                    <jats:title>Purpose<\/jats:title>\n                    <jats:p>To evaluate the accuracy of a wrist-based heart rate (HR) monitor at different exercise intensities across different skin tones.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec id=\"sec002\">\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>Using a cross-sectional design, we compared HR measures from the wrist-based photoplethysmography Fitbit Charge 5 to the Polar H10 chest strap at rest and during the YMCA Protocol using a recumbent cycle ergometer. Participant were grouped into three skin tone categories: light (Fitzpatrick Scale Skin Types 1+2), medium (Types 3+4), and darker skin tone (Types 5+6). HR measures using the Polar chest strap during the exercise test were categorized as &lt;40%, 40\u201360%, or &gt;60% HR reserve (HRR). Absolute error in beats per minute (bpm) between the two devices was calculated for each measure. A linear mixed effects model was used to assess interaction effects between skin tone and exercise intensity, with participants as the random effect. Bland-Altman plots were used for visual analyses.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec id=\"sec003\">\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>Twenty-five participants [mean (SD): 25.8 (1.9) years old; 64% female] were included with 495 observations of simultaneous Fitbit and Polar HR recordings collected during exercise. During exercise, we observed a statistically significant interaction effect between skin tone and exercise intensity. Compared with light skin tone at &lt;40% HRR, mean error was greater for medium skin tone at &gt;60% HRR [mean error (95%CI): 11.8 (5.6\u201317.9) bpm, p&lt;0.001] and darker skin tone at 40\u201360% HRR [7.6 (1.7\u201313.5) bpm, p = 0.011] and &gt;60% HRR [11.7 (5.3\u201318.0) bpm, p&lt;0.001].<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec id=\"sec004\">\n                    <jats:title>Conclusion<\/jats:title>\n                    <jats:p>HR measurement error using a wrist-based device was greater with increasing exercise intensity for people with darker skin tones.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1371\/journal.pone.0318724","type":"journal-article","created":{"date-parts":[[2025,2,10]],"date-time":"2025-02-10T13:26:42Z","timestamp":1739194002000},"page":"e0318724","update-policy":"https:\/\/doi.org\/10.1371\/journal.pone.corrections_policy","source":"Crossref","is-referenced-by-count":21,"title":["Validity of heart rate measurements in wrist-based monitors across skin tones during exercise"],"prefix":"10.1371","volume":"20","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-8725-8036","authenticated-orcid":true,"given":"Stanley Hughwa","family":"Hung","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kelsey","family":"Serwa","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Gillian","family":"Rosenthal","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2093-0788","authenticated-orcid":true,"given":"Janice J.","family":"Eng","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"340","published-online":{"date-parts":[[2025,2,10]]},"reference":[{"key":"pone.0318724.ref001","doi-asserted-by":"crossref","first-page":"550","DOI":"10.1136\/bjsm.2009.059808","article-title":"Evidence on the effects of exercise therapy in the treatment of chronic disease.","volume":"43","author":"UM Kujala","year":"2009","journal-title":"Br J Sports Med"},{"key":"pone.0318724.ref002","doi-asserted-by":"crossref","first-page":"801","DOI":"10.1503\/cmaj.051351","article-title":"Health benefits of physical activity: the evidence.","volume":"174","author":"DER Warburton","year":"2006","journal-title":"CMAJ."},{"key":"pone.0318724.ref003","doi-asserted-by":"crossref","first-page":"3","DOI":"10.1111\/j.1600-0838.2006.00520.x","article-title":"Evidence for prescribing exercise as therapy in chronic disease.","volume":"16","author":"BK Pedersen","year":"2006","journal-title":"Scand J Med Sci Sports"},{"key":"pone.0318724.ref004","doi-asserted-by":"crossref","first-page":"1729","DOI":"10.1007\/s40279-020-01322-8","article-title":"An Examination and Critique of Current Methods to Determine Exercise Intensity.","volume":"50","author":"NA Jamnick","year":"2020","journal-title":"Sports Med."},{"key":"pone.0318724.ref005","doi-asserted-by":"crossref","first-page":"49","DOI":"10.1093\/ehjdh\/ztab011","article-title":"ESC working group on e-cardiology position paper: use of commercially available wearable technology for heart rate and activity tracking in primary and secondary cardiovascular prevention\u2014in collaboration with the European Heart Rhythm Association, European Association of Preventive Cardiology, Association of Cardiovascular Nursing and Allied Professionals, Patient Forum, and the Digital Health Committee","volume":"2","author":"MT Jensen","year":"2021","journal-title":"Eur Heart J Digit Health"},{"key":"pone.0318724.ref006","doi-asserted-by":"crossref","first-page":"66","DOI":"10.3390\/jfmk9020066","article-title":"Net Heart Rate for Estimating Oxygen Consumption in Active Adults.","volume":"9","author":"JA Bragada","year":"2024","journal-title":"Journal of Functional Morphology and Kinesiology"},{"issue":"Suppl","key":"pone.0318724.ref007","first-page":"S3","volume":"16","author":"RM Laukkanen","year":"1998","journal-title":"Heart rate monitors: state of the art. 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