{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,26]],"date-time":"2026-06-26T01:30:32Z","timestamp":1782437432377,"version":"3.54.5"},"reference-count":47,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2023,4,25]],"date-time":"2023-04-25T00:00:00Z","timestamp":1682380800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"King Abdulaziz University, Jeddah, Saudi Arabia"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>This study\u2019s aim was to assess FreeStyle Libre Flash glucose monitoring (FGM) performance during an oral glucose tolerance test (OGTT) and treadmill exercise in healthy adolescents. This should advance the feasibility and utility of user-friendly technologies for metabolic assessments in adolescents. Seventeen healthy adolescents (nine girls aged 12.8 \u00b1 0.9 years) performed an OGTT and submaximal and maximal treadmill exercise tests in a laboratory setting. The scanned interstitial fluid glucose concentration ([ISFG]) obtained by FGM was compared against finger-prick capillary plasma glucose concentration ([CPG]) at 0 (pre-OGTT), \u221215, \u221230, \u221260, \u2212120 min post-OGTT, pre-, mid-, post- submaximal exercise, and pre- and post- maximal exercise. Overall mean absolute relative difference (MARD) was 13.1 \u00b1 8.5%, and 68% (n = 113) of the paired glucose data met the ISO 15197:2013 criteria. For clinical accuracy, 84% and 16% of FGM readings were within zones A and B in the Consensus Error Grid (CEG), respectively, which met the ISO 15197:2013 criteria of having at least 99% of results within these zones. Scanned [ISFG] were statistically lower than [CPG] at 15 (\u22121.16 mmol\u2219L\u22121, p &lt; 0.001) and 30 min (\u22120.74 mmol\u2219L\u22121, p = 0.041) post-OGTT. Yet, post-OGTT glycaemic responses assessed by total and incremental areas under the curve (AUCs) were not significantly different, with trivial to small effect sizes (p \u2265 0.084, d = 0.14\u20130.45). Further, [ISFGs] were not different from [CPGs] during submaximal and maximal exercise tests (interaction p \u2265 0.614). FGM can be a feasible alternative to reflect postprandial glycaemia (AUCs) in healthy adolescents who may not endure repeated finger pricks.<\/jats:p>","DOI":"10.3390\/s23094249","type":"journal-article","created":{"date-parts":[[2023,4,25]],"date-time":"2023-04-25T01:37:01Z","timestamp":1682386621000},"page":"4249","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":10,"title":["Performance of the FreeStyle Libre Flash Glucose Monitoring System during an Oral Glucose Tolerance Test and Exercise in Healthy Adolescents"],"prefix":"10.3390","volume":"23","author":[{"given":"Sahar","family":"Afeef","sequence":"first","affiliation":[{"name":"School of Sport, Exercise and Health Sciences, Loughborough University, Loughborough LE11 3TU, UK"},{"name":"Clinical Nutrition Department, Faculty of Applied Medical Sciences, King Abdulaziz University, Jeddah 21589, Saudi Arabia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6269-1538","authenticated-orcid":false,"given":"Keith","family":"Tolfrey","sequence":"additional","affiliation":[{"name":"School of Sport, Exercise and Health Sciences, Loughborough University, Loughborough LE11 3TU, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4167-4100","authenticated-orcid":false,"given":"Julia K.","family":"Zakrzewski-Fruer","sequence":"additional","affiliation":[{"name":"Institute for Sport and Physical Activity Research, University of Bedfordshire, Bedford MK41 9EA, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2227-0680","authenticated-orcid":false,"given":"Laura A.","family":"Barrett","sequence":"additional","affiliation":[{"name":"School of Sport, Exercise and Health Sciences, Loughborough University, Loughborough LE11 3TU, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2023,4,25]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"923","DOI":"10.1111\/j.1467-789X.2012.01011.x","article-title":"Impact of postprandial glycaemia on health and prevention of disease","volume":"13","author":"Blaak","year":"2012","journal-title":"Obes. 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