{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,30]],"date-time":"2026-03-30T16:48:51Z","timestamp":1774889331631,"version":"3.50.1"},"reference-count":45,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2021,1,6]],"date-time":"2021-01-06T00:00:00Z","timestamp":1609891200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Nutrients"],"abstract":"<jats:p>Low carbohydrate, high fat (LCHF) diets are followed by athletes, but questions remain regarding effects of LCHF on metabolic adaptation, exercise-induced stress, immune function and their time-course. In this cross-over study, 14 recreational male athletes (32.9 \u00b1 8.2 years, VO2max 57.3 \u00b1 5.8 mL\/kg\/min) followed a two week LCHF diet (&lt;10 En% carbohydrates (CHO), ~75En% Fat) and a two week HC diet (&gt;50 En% CHO), in random order, with a wash-out period of &gt;2 weeks in between. After 2 days and 2 weeks on either diet, participants performed cycle ergometry for 90 min at 60%Wmax. Blood samples for analysis of cortisol, free fatty acids (FFA), glucose and ketones, and saliva samples for immunoglobin A (s-IgA) were collected at different time points before and after exercise. The LCHF diet resulted in higher FFA, higher ketones and lower glucose levels compared to the HC diet (p &lt; 0.05). Exercise-induced cortisol response was higher after 2 days on the LCHF diet (822 \u00b1 215 nmol\/L) compared to 2 weeks on the LCHF diet (669 \u00b1 243 nmol\/L, p = 0.004) and compared to both test days following the HC diet (609 \u00b1 208 and 555 \u00b1 173 nmol\/L, both p &lt; 0.001). Workload was lower, and perceived exertion higher, on the LCHF diet compared to the HC diet on both occasions. A drop in s-IgA following exercise was not seen after 2 days on the LCHF diet, in contrast to the HC diet. In conclusion, the LCHF diet resulted in reduced workload with metabolic effects and a pronounced exercise-induced cortisol response after 2 days. Although indications of adaptation were seen after 2 weeks on the LCHF diet, work output was still lower.<\/jats:p>","DOI":"10.3390\/nu13010157","type":"journal-article","created":{"date-parts":[[2021,1,6]],"date-time":"2021-01-06T09:15:16Z","timestamp":1609924516000},"page":"157","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":16,"title":["A 2 Week Cross-over Intervention with a Low Carbohydrate, High Fat Diet Compared to a High Carbohydrate Diet Attenuates Exercise-Induced Cortisol Response, but Not the Reduction of Exercise Capacity, in Recreational Athletes"],"prefix":"10.3390","volume":"13","author":[{"given":"Rieneke","family":"Terink","sequence":"first","affiliation":[{"name":"Division of Human Nutrition and Health, Wageningen University &amp; Research (WUR), 6700 AH Wageningen, The Netherlands"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7935-8261","authenticated-orcid":false,"given":"Renger F.","family":"Witkamp","sequence":"additional","affiliation":[{"name":"Division of Human Nutrition and Health, Wageningen University &amp; Research (WUR), 6700 AH Wageningen, The Netherlands"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Maria T. E.","family":"Hopman","sequence":"additional","affiliation":[{"name":"Department of Physiology, Radboud University Nijmegen, 6525 GA Nijmegen, The Netherlands"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7986-575X","authenticated-orcid":false,"given":"Els","family":"Siebelink","sequence":"additional","affiliation":[{"name":"Division of Human Nutrition and Health, Wageningen University &amp; Research (WUR), 6700 AH Wageningen, The Netherlands"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6236-7092","authenticated-orcid":false,"given":"Huub F. J.","family":"Savelkoul","sequence":"additional","affiliation":[{"name":"Cell Biology and Immunology Group, Wageningen University &amp; Research (WUR), 6700 AH Wageningen, The Netherlands"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9725-5709","authenticated-orcid":false,"given":"Marco","family":"Mensink","sequence":"additional","affiliation":[{"name":"Division of Human Nutrition and Health, Wageningen University &amp; Research (WUR), 6700 AH Wageningen, The Netherlands"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2021,1,6]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Burke, L.M. (2020). Ketogenic low-CHO, high-fat diet: The future of elite endurance sport?. J. 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