{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,14]],"date-time":"2026-10-14T03:05:15Z","timestamp":1791947115873,"version":"4.3.4"},"reference-count":33,"publisher":"Public Library of Science (PLoS)","issue":"3","license":[{"start":{"date-parts":[[2026,3,6]],"date-time":"2026-03-06T00:00:00Z","timestamp":1772755200000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["www.plosone.org"],"crossmark-restriction":false},"short-container-title":["PLoS One"],"abstract":"<jats:sec id=\"sec001\">\n                    <jats:title>Objectives<\/jats:title>\n                    <jats:p>This study investigated the physiological behavior of the running velocity associated with the Minimum Lactate Steady State (vMLaSS), derived from a 6\u2009\u00d7\u2009800-m interval protocol, and examined whether this intensity produced stable metabolic and lactate responses during a 30-minute constant-load validation run in trained endurance runners.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec id=\"sec002\">\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>\n                      Fifteen trained male middle- and long-distance runners completed a graded treadmill test to determine maximal oxygen uptake. Following a supramaximal sprint to induce hyperlactatemia, each athlete performed a 30-minute constant-load run at a velocity derived from the lactate-minimum approach. Following a supramaximal sprint to induce hyperlactatemia, each athlete performed a 30-minute constant-speed run at their individually determined MLaSS velocity. Blood lactate samples were collected at 10-minute intervals, and breath-by-breath cardiopulmonary variables were continuously recorded. Lactate kinetics were analyzed using a Friedman test with Wilcoxon signed-rank post-hoc comparisons (\n                      <jats:italic>p<\/jats:italic>\n                      \u2009&lt;\u20090.05).\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec id=\"sec003\">\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>\n                      Blood lactate exhibited significant time-dependent fluctuations during the 30-minute trial (Friedman \u03c7\u00b2 (3) = 28.72,\n                      <jats:italic>p<\/jats:italic>\n                      \u2009&lt;\u20090.001). Lactate increased sharply by minute 10, declined at minute 20, and rose again at minute 30, exceeding the classical MLSS criterion of \u22641 mmol\u00b7L\u2009\u207b\u2009\u00b9 change during the final 20 minutes. In contrast, cardiopulmonary variables remained stable throughout V\u0307O\u2082 (3.43\u2009\u00b1\u20090.11 L\u00b7min\u2009\u207b\u2009\u00b9;\n                      <jats:italic>p<\/jats:italic>\n                      \u2009=\u20090.86) and V\u0307CO\u2082 (3.21\u2009\u00b1\u20090.14 L\u00b7min\u2009\u207b\u2009\u00b9;\n                      <jats:italic>p<\/jats:italic>\n                      \u2009=\u20090.91). Carbohydrate oxidation predominated (214.5\u2009\u00b1\u200919.3 g\u00b7h\u2009\u207b\u2009\u00b9), whereas fat oxidation remained minimal (\u20130.9\u2009\u00b1\u20092.7 g\u00b7h\u2009\u207b\u2009\u00b9).\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec id=\"sec004\">\n                    <jats:title>Conclusion<\/jats:title>\n                    <jats:p>Despite stable cardiorespiratory and substrate-utilization profiles, the significant variability in blood lactate concentration during the 30-minute constant-load run indicates that the running velocity derived from the lactate-minimum approach did not elicit a lactate steady state in this trained cohort. These findings suggest that physiological responses at the MLaSS-derived intensity may differ from classical steady-state expectations in highly trained endurance runners and highlight the need for direct MLSS verification in future studies.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1371\/journal.pone.0344573","type":"journal-article","created":{"date-parts":[[2026,3,6]],"date-time":"2026-03-06T18:36:26Z","timestamp":1772822186000},"page":"e0344573","update-policy":"https:\/\/doi.org\/10.1371\/journal.pone.corrections_policy","source":"Crossref","is-referenced-by-count":3,"title":["Assessing lactate stability at the minimum lactate steady state velocity in male trained middle-distance runners"],"prefix":"10.1371","volume":"21","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-5379-3567","authenticated-orcid":true,"given":"Seyed 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Whipp","year":"1987","journal-title":"Advances in Cardiology"},{"issue":"5","key":"pone.0344573.ref004","doi-asserted-by":"crossref","first-page":"620","DOI":"10.1249\/00005768-199305000-00015","article-title":"Estimation of an individual equilibrium between lactate production and catabolism during exercise","volume":"25","author":"U Tegtbur","year":"1993","journal-title":"Med Sci Sports Exerc"},{"issue":"8","key":"pone.0344573.ref005","doi-asserted-by":"crossref","first-page":"1304","DOI":"10.1097\/00005768-199808000-00020","article-title":"The validity of the lactate minimum test for determination of the maximal lactate steady state","volume":"30","author":"AM Jones","year":"1998","journal-title":"Med Sci Sports Exerc"},{"issue":"4","key":"pone.0344573.ref006","first-page":"441","article-title":"Relationships and significance of lactate minimum, critical velocity, heart rate deflection and 3 000 m track-tests for running","volume":"45","author":"HG Sim\u00f5es","year":"2005","journal-title":"J Sports Med Phys Fitness"},{"issue":"1","key":"pone.0344573.ref007","doi-asserted-by":"crossref","first-page":"34","DOI":"10.1007\/s004210050555","article-title":"Blood glucose responses in humans mirror lactate responses for individual anaerobic threshold and for lactate minimum in track tests","volume":"80","author":"HG Sim\u00f5es","year":"1999","journal-title":"Eur J Appl Physiol Occup Physiol"},{"key":"pone.0344573.ref008","first-page":"389","article-title":"The Lactate Minimum Test: Concept, Methodological Aspects and Insights for Future Investigations in Human and Animal Models","volume":"8","author":"LHD Messias","year":"2017","journal-title":"Front Physiol"},{"issue":"3","key":"pone.0344573.ref009","doi-asserted-by":"crossref","first-page":"232","DOI":"10.1139\/h02-014","article-title":"The lactate minimum test for cycling: estimation of the maximal lactate steady state","volume":"27","author":"BR 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Sietsema","year":"2020"},{"issue":"2","key":"pone.0344573.ref013","doi-asserted-by":"crossref","first-page":"273","DOI":"10.1007\/BF00422166","article-title":"A simple method for measurement of mechanical power in jumping","volume":"50","author":"C Bosco","year":"1983","journal-title":"Eur J Appl Physiol Occup Physiol"},{"key":"pone.0344573.ref014","article-title":"International Society for the Advancement of Kinanthropometry (ISAK) Global: International Accreditation Scheme of the Competent Anthropometrist","volume":"22","author":"VS Silva","year":"2020","journal-title":"Revista Brasileira de Cineantropometria & Desempenho Humano"},{"issue":"4","key":"pone.0344573.ref015","doi-asserted-by":"crossref","first-page":"321","DOI":"10.1080\/02640419608727717","article-title":"A 1% treadmill grade most accurately reflects the energetic cost of outdoor running","volume":"14","author":"AM Jones","year":"1996","journal-title":"J Sports Sci"},{"issue":"2","key":"pone.0344573.ref016","first-page":"628","article-title":"Calculation of substrate oxidation rates in vivo from gaseous exchange","volume":"55","author":"KN Frayn","year":"1983","journal-title":"J Appl Physiol Respir Environ Exerc Physiol"},{"key":"pone.0344573.ref017","volume-title":"The effect size","author":"J Cohen","year":"1988"},{"issue":"1","key":"pone.0344573.ref018","doi-asserted-by":"crossref","first-page":"151","DOI":"10.1113\/jphysiol.2007.142109","article-title":"Similar metabolic adaptations during exercise after low volume sprint interval and traditional endurance training in humans","volume":"586","author":"KA Burgomaster","year":"2008","journal-title":"J Physiol"},{"issue":"16","key":"pone.0344573.ref019","doi-asserted-by":"crossref","DOI":"10.3390\/jcm13164812","article-title":"Sex Differences in the Energy System Contribution during Sprint Exercise in Speed-Power and Endurance Athletes","volume":"13","author":"D Archacki","year":"2024","journal-title":"J Clin Med"},{"issue":"6","key":"pone.0344573.ref020","doi-asserted-by":"crossref","first-page":"469","DOI":"10.2165\/00007256-200939060-00003","article-title":"Lactate threshold concepts: how valid are they?","volume":"39","author":"O Faude","year":"2009","journal-title":"Sports Med"},{"issue":"10","key":"pone.0344573.ref021","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"},{"issue":"3","key":"pone.0344573.ref022","doi-asserted-by":"crossref","first-page":"899","DOI":"10.1152\/jappl.2000.89.3.899","article-title":"Oxygen uptake kinetics in treadmill running and cycle ergometry: a comparison","volume":"89","author":"H Carter","year":"2000","journal-title":"J Appl Physiol 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Wahl","year":"2017","journal-title":"J Strength Cond Res"},{"issue":"3","key":"pone.0344573.ref026","first-page":"279","article-title":"The lactate minimum test protocol provides valid measures of cycle ergometer VO(2)peak","volume":"43","author":"R Dantas De Luca","year":"2003","journal-title":"J Sports Med Phys Fitness"},{"issue":"10","key":"pone.0344573.ref027","doi-asserted-by":"crossref","first-page":"2927","DOI":"10.1519\/JSC.0000000000000490","article-title":"Hyperlactemia induction modes affect the lactate minimum power and physiological responses in cycling","volume":"28","author":"AM Zagatto","year":"2014","journal-title":"J Strength Cond Res"},{"issue":"14","key":"pone.0344573.ref028","doi-asserted-by":"crossref","first-page":"3213","DOI":"10.3390\/nu15143213","article-title":"Concepts of lactate metabolic clearance rate and lactate clamp for metabolic inquiry: a mini-review","volume":"15","author":"CAW 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