{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,6]],"date-time":"2026-05-06T22:40:40Z","timestamp":1778107240845,"version":"3.51.4"},"reference-count":20,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2020,10,8]],"date-time":"2020-10-08T00:00:00Z","timestamp":1602115200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Metabolites"],"abstract":"<jats:p>Understanding the metabolic processes in energy metabolism, particularly during fasted exercise, is a growing area of research. Previous work has focused on measuring metabolites pre and post exercise. This can provide information about the final state of energy metabolism in the participants, but it does not show how these processes vary during the exercise and any subsequent post-exercise period. To address this, the work described here took fasted participants and subjected them to an exercise and rest protocol under laboratory settings, which allowed for breath and blood sampling both pre, during and post exercise. Analysis of the data produced from both the physiological measurements and the untargeted metabolomics measurements showed clear switching between glycolytic and ketolytic metabolism, with the liquid chromatography-mass spectrometry (LC-MS) data showing the separate stages of ketolytic metabolism, notably the transport, release and breakdown of long chain fatty acids. Several signals, putatively identified as short peptides, were observed to change in a pattern similar to that of the ketolytic metabolites. This work highlights the power of untargeted metabolomic methods as an investigative tool for exercise science, both to follow known processes in a more complete way and discover possible novel biomarkers.<\/jats:p>","DOI":"10.3390\/metabo10100399","type":"journal-article","created":{"date-parts":[[2020,10,8]],"date-time":"2020-10-08T10:22:25Z","timestamp":1602152545000},"page":"399","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":13,"title":["Running on Empty: A Metabolomics Approach to Investigating Changing Energy Metabolism during Fasted Exercise and Rest"],"prefix":"10.3390","volume":"10","author":[{"given":"Gavin","family":"Blackburn","sequence":"first","affiliation":[{"name":"Glasgow Polyomics, Wolfson Wohl Cancer Research Centre, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow G61 1BD, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Joshua","family":"Hay","sequence":"additional","affiliation":[{"name":"Center for Preventive Cardiology, Knight Cardiovascular Institute, Oregon Health &amp; Science University, 3181 SW Sam Jackson Park Rd. Portland, OR 97239, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Christine","family":"Skagen","sequence":"additional","affiliation":[{"name":"Muscle Research Group, Department of Pharmacy, University of Oslo, Sem S\u00e6lands vei 3, 0371 Oslo, Norway"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Elizabeth","family":"Paul","sequence":"additional","affiliation":[{"name":"BHF Glasgow Cardiovascular Research Centre (GCRC), Institute of Cardiovascular &amp; Medical Sciences, University of Glasgow, 126 University Place, Glasgow G12 8TA, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8792-7615","authenticated-orcid":false,"given":"Fiona","family":"Achcar","sequence":"additional","affiliation":[{"name":"Wellcome Centre for Integrative Parasitology, Institute of Infection, Immunity and Inflammation, University of Glasgow, 126 University Place, Glasgow G12 8TA, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"John","family":"Wilson","sequence":"additional","affiliation":[{"name":"BHF Glasgow Cardiovascular Research Centre (GCRC), Institute of Cardiovascular &amp; Medical Sciences, University of Glasgow, 126 University Place, Glasgow G12 8TA, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0980-6863","authenticated-orcid":false,"given":"Cameron","family":"Best","sequence":"additional","affiliation":[{"name":"Institute of Infection, Immunity and Inflammation, University of Glasgow, Sir Graeme Davis Building, 126 University Place, Glasgow G12 8TA, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Erin","family":"Manson","sequence":"additional","affiliation":[{"name":"Glasgow Polyomics, Wolfson Wohl Cancer Research Centre, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow G61 1BD, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Karl","family":"Burgess","sequence":"additional","affiliation":[{"name":"Institute of Quantitative Biology, Biochemistry and Biotechnology, The University of Edinburgh, Edinburgh EH9 3FF, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Michael P.","family":"Barrett","sequence":"additional","affiliation":[{"name":"Glasgow Polyomics, Wolfson Wohl Cancer Research Centre, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow G61 1BD, UK"},{"name":"Wellcome Centre for Integrative Parasitology, Institute of Infection, Immunity and Inflammation, University of Glasgow, 126 University Place, Glasgow G12 8TA, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3615-0986","authenticated-orcid":false,"given":"Jason M. R.","family":"Gill","sequence":"additional","affiliation":[{"name":"BHF Glasgow Cardiovascular Research Centre (GCRC), Institute of Cardiovascular &amp; Medical Sciences, University of Glasgow, 126 University Place, Glasgow G12 8TA, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2020,10,8]]},"reference":[{"key":"ref_1","first-page":"342","article-title":"SnapShot: Exercise Metabolism. Cell Metabolism","volume":"24","author":"Egan","year":"2016","journal-title":"Cell Press"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"33ra37","DOI":"10.1126\/scitranslmed.3001006","article-title":"Metabolic signatures of exercise in human plasma","volume":"2","author":"Lewis","year":"2010","journal-title":"Sci. Transl. 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