{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,26]],"date-time":"2026-10-26T10:33:45Z","timestamp":1793010825808,"version":"4.5.0"},"reference-count":25,"publisher":"Wiley","issue":"5","license":[{"start":{"date-parts":[[2026,9,2]],"date-time":"2026-09-02T00:00:00Z","timestamp":1788307200000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"},{"start":{"date-parts":[[2026,9,2]],"date-time":"2026-09-02T00:00:00Z","timestamp":1788307200000},"content-version":"tdm","delay-in-days":0,"URL":"http:\/\/doi.wiley.com\/10.1002\/tdm_license_1.1"}],"content-domain":{"domain":["onlinelibrary.wiley.com"],"crossmark-restriction":true},"short-container-title":["J cachexia sarcopenia muscle"],"published-print":{"date-parts":[[2026,10]]},"abstract":"<jats:title>ABSTRACT<\/jats:title>\n                  <jats:sec>\n                    <jats:title>Background<\/jats:title>\n                    <jats:p>Age\u2010related declines in energy metabolism, muscle strength and physical performance have been linked to lower mitochondrial respiratory capacity. Peripheral blood mononuclear cell (PBMC) respiration offers a minimally invasive marker of systemic bioenergetics, yet its relationship to whole\u2010body metabolic flexibility remains unclear. This study examined whether PBMC respiratory capacity is associated with substrate utilization during submaximal exercise, muscle strength and physical function in healthy older adults.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>\n                      PBMC mitochondrial respiratory capacity was quantified by high\u2010resolution respirometry assessing ROUTINE, LEAK and MAX states. Postprandial substrate oxidation during steady\u2010state treadmill walking at 60% of VO\n                      <jats:sub>2<\/jats:sub>\n                      max (oxygen uptake) was quantified by indirect calorimetry, and fat and carbohydrate oxidation rates were calculated using standard stoichiometric equations. Metabolic flexibility was defined as lower respiratory exchange ratio (RER) and higher relative fat oxidation at a fixed workload. Muscle strength was determined by handgrip dynamometry and one\u2010repetition maximum leg extension. Physical function was evaluated by gait speed and five\u2010repetition chair rise time. Associations were tested with linear and logistic regression adjusted for age, sex, skeletal muscle index, physical activity and high\u2010sensitive C\u2010reactive protein concentrations. Exploratory K\u2010means clustering identified mitochondrial respiration phenotypes.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>\n                      Fifty community\u2010dwelling older adults (22 men, 28 women; age 70\u2009\u00b1\u20094\u2009years) were examined. Higher ROUTINE respiration was correlated with RER (rho\u2009=\u2009\u22120.335,\n                      <jats:italic>p<\/jats:italic>\n                      \u2009=\u20090.020), fat utilization (rho\u2009=\u2009\u22120.334,\n                      <jats:italic>p<\/jats:italic>\n                      \u2009=\u20090.019), grip strength (rho\u2009=\u20090.302,\n                      <jats:italic>p<\/jats:italic>\n                      \u2009=\u20090.033) and gait speed (rho\u2009=\u20090.324,\n                      <jats:italic>p<\/jats:italic>\n                      \u2009=\u20090.022). Adjusted regression analyses confirmed the association of ROUTINE respiration with greater fat oxidation (\u03b2\u2009=\u20090.212, 95% CI 0.049; 0.375), lower RER (\u03b2\u2009=\u2009\u22120.160, 95% CI \u22120.300; \u22120.020) and higher gait speed (\u03b2\u2009=\u20090.153, 95% CI 0.028; 0.277). Similar associations were found for ATP\u2010linked respiration. Cluster analysis identified high\u2010 and low\u2010respiration phenotypes. Compared with the high\u2010respiration group the low\u2010respiration group showed lower CMJ height (OR: 0.204, 95% CI 0.055; 0.763) and quadriceps strength (OR: 0.373, 95% CI 0.155; 0.897).\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusions<\/jats:title>\n                    <jats:p>In healthy older adults, higher PBMC ROUTINE respiration was associated with a more fat\u2010dominant substrate utilization profile during submaximal exercise, greater muscle strength and faster gait speed. PBMC respiratory capacity may reflect systemic bioenergetic status relevant to exercise substrate utilization and physical performance in ageing.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1002\/jcsm.70361","type":"journal-article","created":{"date-parts":[[2026,9,3]],"date-time":"2026-09-03T06:12:11Z","timestamp":1788415931000},"update-policy":"https:\/\/doi.org\/10.1002\/crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Mitochondrial Respiration in Peripheral Blood Cells Links to Metabolic Flexibility and Physical Performance in Ageing"],"prefix":"10.1002","volume":"17","author":[{"ORCID":"https:\/\/orcid.org\/0009-0009-1478-5615","authenticated-orcid":false,"given":"Donna","family":"Li","sequence":"first","affiliation":[{"name":"Institute of Nutritional Sciences University of Potsdam  Nuthetal Germany"},{"name":"Department of Nutrition and Gerontology German Institute of Human Nutrition Potsdam\u2010Rehbruecke  Nuthetal Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Catrin","family":"Herpich","sequence":"additional","affiliation":[{"name":"Department of Nutrition and Gerontology German Institute of Human Nutrition Potsdam\u2010Rehbruecke  Nuthetal Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Christopher","family":"Bishop","sequence":"additional","affiliation":[{"name":"Department of Molecular Physiology of Exercise and Nutrition German Institute of Human Nutrition (DifE) Potsdam\u2010Rehbruecke  Nuthetal Germany"},{"name":"German Center for Diabetes Research (DZD)  Munich Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Marie","family":"Aleithe","sequence":"additional","affiliation":[{"name":"Department of Nutrition and Gerontology German Institute of Human Nutrition Potsdam\u2010Rehbruecke  Nuthetal Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Antonia","family":"Peil","sequence":"additional","affiliation":[{"name":"Department of Nutrition and Gerontology German Institute of Human Nutrition Potsdam\u2010Rehbruecke  Nuthetal Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Nele","family":"Kr\u00fcger","sequence":"additional","affiliation":[{"name":"Department of Nutrition and Gerontology German Institute of Human Nutrition Potsdam\u2010Rehbruecke  Nuthetal Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jannes","family":"Felsner","sequence":"additional","affiliation":[{"name":"Department of Nutrition and Gerontology German Institute of Human Nutrition Potsdam\u2010Rehbruecke  Nuthetal Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Lea","family":"G\u00f6ger","sequence":"additional","affiliation":[{"name":"Department of Nutrition and Gerontology German Institute of Human Nutrition Potsdam\u2010Rehbruecke  Nuthetal Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Maximilian","family":"Kleinert","sequence":"additional","affiliation":[{"name":"Institute of Nutritional Sciences University of Potsdam  Nuthetal Germany"},{"name":"Department of Molecular Physiology of Exercise and Nutrition German Institute of Human Nutrition (DifE) Potsdam\u2010Rehbruecke  Nuthetal Germany"},{"name":"German Center for Diabetes Research (DZD)  Munich Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2029-9102","authenticated-orcid":false,"given":"Kristina","family":"Norman","sequence":"additional","affiliation":[{"name":"Institute of Nutritional Sciences University of Potsdam  Nuthetal Germany"},{"name":"Department of Nutrition and Gerontology German Institute of Human Nutrition Potsdam\u2010Rehbruecke  Nuthetal Germany"},{"name":"Department of Geriatrics and Medical Gerontology Charit\u00e9\u2014Universit\u00e4tsmedizin Berlin, Corporate Member of Freie Universit\u00e4t Berlin and Humboldt\u2010Universit\u00e4t zu Berlin  Berlin Germany"},{"name":"German Center for Cardiovascular Research (DZHK), Partner Site Berlin  Berlin Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"311","published-online":{"date-parts":[[2026,9,2]]},"reference":[{"key":"e_1_2_11_2_1","doi-asserted-by":"publisher","DOI":"10.1016\/S0140-6736(19)31138-9"},{"key":"e_1_2_11_3_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.archger.2020.104109"},{"key":"e_1_2_11_4_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.cmet.2017.04.015"},{"key":"e_1_2_11_5_1","doi-asserted-by":"publisher","DOI":"10.1093\/gerona\/glv070"},{"key":"e_1_2_11_6_1","doi-asserted-by":"publisher","DOI":"10.1111\/j.1600-0838.2005.00480.x"},{"key":"e_1_2_11_7_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.cmet.2023.08.001"},{"key":"e_1_2_11_8_1","doi-asserted-by":"publisher","DOI":"10.1002\/jcsm.12932"},{"key":"e_1_2_11_9_1","doi-asserted-by":"publisher","DOI":"10.1093\/gerona\/gls196"},{"key":"e_1_2_11_10_1","doi-asserted-by":"publisher","DOI":"10.2337\/db11-1832"},{"key":"e_1_2_11_11_1","doi-asserted-by":"publisher","DOI":"10.1073\/pnas.0501559102"},{"key":"e_1_2_11_12_1","doi-asserted-by":"publisher","DOI":"10.1042\/CS20140101"},{"key":"e_1_2_11_13_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.exger.2020.111177"},{"key":"e_1_2_11_14_1","doi-asserted-by":"publisher","DOI":"10.1177\/1358863X14521315"},{"key":"e_1_2_11_15_1","doi-asserted-by":"publisher","DOI":"10.1038\/srep10229"},{"key":"e_1_2_11_16_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.exger.2015.07.015"},{"key":"e_1_2_11_17_1","doi-asserted-by":"publisher","DOI":"10.1093\/gerona\/glu096"},{"key":"e_1_2_11_18_1","doi-asserted-by":"publisher","DOI":"10.1249\/01.MSS.0000078924.61453.FB"},{"key":"e_1_2_11_19_1","doi-asserted-by":"publisher","DOI":"10.1249\/01.mss.0000193561.64152"},{"key":"e_1_2_11_20_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.pcad.2017.03.002"},{"key":"e_1_2_11_21_1","doi-asserted-by":"publisher","DOI":"10.1152\/jappl.1983.55.2.628"},{"key":"e_1_2_11_22_1","doi-asserted-by":"publisher","DOI":"10.1097\/00005768-200201000-00015"},{"key":"e_1_2_11_23_1","doi-asserted-by":"publisher","DOI":"10.1113\/jphysiol.2005.102178"},{"key":"e_1_2_11_24_1","doi-asserted-by":"publisher","DOI":"10.1002\/ajhb.24212"},{"key":"e_1_2_11_25_1","unstructured":"E.Gnaiger E.Aasander Frostner N.Abdul Karim et\u00a0al. 2019. \u201cMitochondrial Respiratory States and Rates \u201d MitoFit Preprint Archives https:\/\/doi.org\/10.26124\/MITOFIT:190001.V3."},{"key":"e_1_2_11_26_1","doi-asserted-by":"publisher","DOI":"10.1042\/BJ20110162"}],"container-title":["Journal of Cachexia, Sarcopenia and Muscle"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/pdf\/10.1002\/jcsm.70361","content-type":"application\/pdf","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/full-xml\/10.1002\/jcsm.70361","content-type":"application\/xml","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/pdf\/10.1002\/jcsm.70361","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,10,26]],"date-time":"2026-10-26T09:49:33Z","timestamp":1793008173000},"score":1,"resource":{"primary":{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/10.1002\/jcsm.70361"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,9,2]]},"references-count":25,"journal-issue":{"issue":"5","published-print":{"date-parts":[[2026,10]]}},"alternative-id":["10.1002\/jcsm.70361"],"URL":"https:\/\/doi.org\/10.1002\/jcsm.70361","archive":["Portico"],"relation":{},"ISSN":["2190-5991","2190-6009"],"issn-type":[{"value":"2190-5991","type":"print"},{"value":"2190-6009","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,9,2]]},"assertion":[{"value":"2025-11-21","order":0,"name":"received","label":"Received","group":{"name":"publication_history","label":"Publication History"}},{"value":"2026-07-21","order":2,"name":"accepted","label":"Accepted","group":{"name":"publication_history","label":"Publication History"}},{"value":"2026-09-02","order":3,"name":"published","label":"Published","group":{"name":"publication_history","label":"Publication History"}}],"article-number":"e70361"}}