{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,14]],"date-time":"2026-10-14T16:48:54Z","timestamp":1791996534980,"version":"4.4.0"},"reference-count":23,"publisher":"The Company of Biologists","issue":"4","license":[{"start":{"date-parts":[[2026,4,22]],"date-time":"2026-04-22T00:00:00Z","timestamp":1776816000000},"content-version":"vor","delay-in-days":7,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0"}],"funder":[{"DOI":"10.13039\/501100001652","name":"Friedrich-Alexander-Universit\u00e4t Erlangen-N\u00fcrnberg","doi-asserted-by":"crossref","id":[{"id":"10.13039\/501100001652","id-type":"DOI","asserted-by":"crossref"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2026,4,15]]},"abstract":"<jats:title>ABSTRACT<\/jats:title>\n                  <jats:p>This study aimed to validate a handheld capillary blood lactate analyzer (Lactate Express) against a reference (EKF Biosen C-Line) and assess its impact on lactate thresholds. Thirty-five participants completed incremental running or cycling tests with capillary sampling. Lactate was measured with the Lactate Express and an EKF Biosen C-Line analyzer, yielding 231 paired samples (0.5\u201314.2\u2005mmol\u2005l\u22121). Agreement was evaluated using intraclass correlation, Lin's concordance correlation, mean absolute error, and Bland-Altman analyses overall and within &amp;lt;1, 1\u20134, and &amp;gt;4\u2005mmol\u2005l\u22121. Thresholds at 2 and 4\u2005mmol\u2005l\u22121 were compared between devices for 18 participants in both exercise modes. Overall agreement was high (intraclass correlation coefficient 0.98), but Bland-Altman analysis showed a bias of \u22120.29\u2005mmol\u2005l\u22121 with concentration dependent behavior. Bias was negligible within the 1\u20134\u2005mmol\u2005l\u22121 range (\u22120.05\u2005mmol\u2005l\u22121), positive at concentrations &amp;lt;1\u2005mmol\u2005l\u22121 (0.29\u2005mmol\u2005l\u22121) with pronounced underestimation at concentrations &amp;gt;4\u2005mmol\u2005l\u22121 (\u22121.03\u2005mmol\u2005l\u22121). Differences in 2 and 4\u2005mmol\u2005l\u22121 thresholds were small and non-systematic. The Lactate Express demonstrates good relative and absolute agreement within the 1\u20134\u2005mmol\u2005l\u22121 range relevant for threshold-based training prescription, but exhibits substantial and systematic bias at both low and high lactate concentrations. The device may provide broadly comparable threshold estimates in some cases but should not be considered interchangeable with the laboratory reference device across the full lactate concentration spectrum.<\/jats:p>","DOI":"10.1242\/bio.062543","type":"journal-article","created":{"date-parts":[[2026,4,22]],"date-time":"2026-04-22T08:13:00Z","timestamp":1776845580000},"source":"Crossref","is-referenced-by-count":1,"title":["Validation of a novel handheld lactate analyzer reveals concentration-dependent bias compared with a laboratory reference device"],"prefix":"10.1242","volume":"15","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-7044-9426","authenticated-orcid":false,"given":"Benedikt","family":"Meixner","sequence":"first","affiliation":[{"name":"Julius-Maximilians-Universit\u00e4t W\u00fcrzburg, Integrative and Experimental Exercise Science and Training 1 , Department of Sport Science, Judenb\u00fchlweg 11, 97082 W\u00fcrzburg ,","place":["Germany"]},{"name":"Friedrich-Alexander-Universit\u00e4t Erlangen-N\u00fcrnberg 2 , Department for Sport Science and Sport, Gebbertstra\u00dfe 123b, 91058 Erlangen , Germany"},{"name":"iq-move Praxis Dr. Fraunberger 3 , Gebbertstra\u00dfe 123b, 91058 Erlangen , Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2771-3030","authenticated-orcid":false,"given":"Manuel","family":"Matzka","sequence":"additional","affiliation":[{"name":"Department of Management and Sport 4 , IST-University of Applied Sciences, 40233 Dusseldorf ,","place":["Germany"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Peter","family":"Renner","sequence":"additional","affiliation":[{"name":"iq-move Praxis Dr. Fraunberger 3 , Gebbertstra\u00dfe 123b, 91058 Erlangen , Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Silvia","family":"Achtzehn","sequence":"additional","affiliation":[{"name":"Schwarz Corporate Solutions KG, Health and Performance 5 , Stiftsbergstra\u00dfe 1, 74172 Neckarsulm , Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4686-8561","authenticated-orcid":false,"given":"Billy","family":"Sperlich","sequence":"additional","affiliation":[{"name":"Julius-Maximilians-Universit\u00e4t W\u00fcrzburg, Integrative and Experimental Exercise Science and Training 1 , Department of Sport Science, Judenb\u00fchlweg 11, 97082 W\u00fcrzburg ,","place":["Germany"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"237","published-online":{"date-parts":[[2026,4,22]]},"reference":[{"key":"2026042204125939400_BIO062543C1","doi-asserted-by":"publisher","first-page":"433","DOI":"10.1055\/s-2003-41180","article-title":"Biological variation in variables associated with exercise training","volume":"24","author":"Bagger","year":"2003","journal-title":"Int. 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