{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,28]],"date-time":"2026-07-28T06:35:12Z","timestamp":1785220512067,"version":"3.55.0"},"reference-count":44,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2024,7,1]],"date-time":"2024-07-01T00:00:00Z","timestamp":1719792000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100010318","name":"University of Manitoba","doi-asserted-by":"publisher","award":["48805"],"award-info":[{"award-number":["48805"]}],"id":[{"id":"10.13039\/100010318","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Muscles"],"abstract":"<jats:p>Myokines released by exercise are identified as factors that can influence a person\u2019s health and wellbeing. While myokine secretion in response to an acute bout of endurance and resistance-type exercise has been examined, the influence of resistance-exercise training on myokines at rest is less well established. Therefore, this study was designed to evaluate a panel of myokines at rest following a 12-week resistance-exercise training program in younger and older males. Participants (n = 15) completed a 12-week progressive resistance-exercise training program supervised by a certified fitness professional. The training protocol targeted all major muscle groups of the upper and lower body. Resting blood samples were collected before and after completion of the training program to determine concentrations of apelin, fibroblast growth factor-21 (FGF-21), interleukin (IL)-4, IL-6, IL-7, IL-15, leukemia inhibitory factor (LIF), and irisin. Two-way repeated ANOVAs were used to compare variables between time-points and age groups. There was a main effect of time found for apelin (p = 0.003) and IL-15 (p &lt; 0.001), while no main effects for group or time were found for the other myokines (all p &gt; 0.05). Age group \u00d7 training status interactions were found for IL-6 (p = 0.04) and irisin (p = 0.014) without pairwise differences for IL-6 (p &gt; 0.05), and younger males had higher concentrations of irisin compared to older males post-training (p = 0.036). Overall, the 12-week resistance-exercise training program significantly increased apelin and IL-15 over time but did not change the other resting myokine concentrations for the younger or older males. However, the higher concentration of irisin in younger versus older males post-training suggests a potential explanation for the anabolic resistance observed with aging.<\/jats:p>","DOI":"10.3390\/muscles3030018","type":"journal-article","created":{"date-parts":[[2024,7,3]],"date-time":"2024-07-03T08:45:34Z","timestamp":1719996334000},"page":"202-211","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":6,"title":["Resting Systemic Irisin Concentrations Are Lower in Older versus Younger Males after 12 Weeks of Resistance-Exercise Training While Apelin and IL-15 Concentrations Were Increased in the Whole Cohort"],"prefix":"10.3390","volume":"3","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-1874-8370","authenticated-orcid":false,"given":"Dean M.","family":"Cordingley","sequence":"first","affiliation":[{"name":"Applied Health Sciences, University of Manitoba, Winnipeg, MB R3T 2N2, Canada"},{"name":"Pan Am Clinic Foundation, 75 Poseidon Bay, Winnipeg, MB R3M 3E4, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Judy E.","family":"Anderson","sequence":"additional","affiliation":[{"name":"Faculty of Science, University of Manitoba, Winnipeg, MB R3T 2N2, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0801-6707","authenticated-orcid":false,"given":"Stephen M.","family":"Cornish","sequence":"additional","affiliation":[{"name":"Applied Health Sciences, University of Manitoba, Winnipeg, MB R3T 2N2, Canada"},{"name":"Faculty of Kinesiology and Recreation Management, University of Manitoba, Winnipeg, MB R3T 2N2, Canada"},{"name":"Centre for Aging, University of Manitoba, Winnipeg, MB R3T 2N2, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2024,7,1]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"112177","DOI":"10.1016\/j.exger.2023.112177","article-title":"Age-Associated Inflammation and Implications for Skeletal Muscle Responses to Exercise","volume":"177","author":"Kunz","year":"2023","journal-title":"Exp. Gerontol."},{"key":"ref_2","first-page":"e00001","article-title":"The Health Benefits of Resistance Exercise: Beyond Hypertrophy and Big Weights","volume":"1","author":"Nunes","year":"2023","journal-title":"Exerc. Sport Mov."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"350","DOI":"10.1007\/s11914-020-00596-1","article-title":"Potential Importance of Immune System Response to Exercise on Aging Muscle and Bone","volume":"18","author":"Cornish","year":"2020","journal-title":"Curr. Osteoporos. Rep."},{"key":"ref_4","doi-asserted-by":"crossref","unstructured":"Zunner, B.E.M., Wachsmuth, N.B., Eckstein, M.L., Scherl, L., Schierbauer, J.R., Haupt, S., Stumpf, C., Reusch, L., and Moser, O. (2022). Myokines and Resistance Training: A Narrative Review. Int. J. Mol. Sci., 23.","DOI":"10.3390\/ijms23073501"},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"607","DOI":"10.1038\/nri3041","article-title":"The Anti-Inflammatory Effects of Exercise: Mechanisms and Implications for the Prevention and Treatment of Disease","volume":"11","author":"Gleeson","year":"2011","journal-title":"Nat. Rev. Immunol."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"105","DOI":"10.1042\/bse0420105","article-title":"The Anti-Inflammatory Effect of Exercise: Its Role in Diabetes and Cardiovascular Disease Control","volume":"42","author":"Pedersen","year":"2006","journal-title":"Essays Biochem."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"2419","DOI":"10.2174\/1389557522666220309161245","article-title":"The Role of IL-6 Released during Exercise to Insulin Sensitivity and Muscle Hypertrophy","volume":"22","year":"2022","journal-title":"Mini Rev. Med. Chem."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"111676","DOI":"10.1016\/j.mce.2022.111676","article-title":"Irisin Reduces Inflammatory Signaling Pathways in Inflammation-Mediated Metabolic Syndrome","volume":"552","author":"Yano","year":"2022","journal-title":"Mol. Cell Endocrinol."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"156303","DOI":"10.1016\/j.cyto.2023.156303","article-title":"Influence of Different Modes of Exercise Training on Inflammatory Markers in Older Adults with and without Chronic Diseases: A Systematic Review and Meta-Analysis","volume":"169","author":"Khalafi","year":"2023","journal-title":"Cytokine"},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"263","DOI":"10.1079\/PNS2004338","article-title":"The Metabolic Role of IL-6 Produced during Exercise: Is IL-6 an Exercise Factor?","volume":"63","author":"Pedersen","year":"2004","journal-title":"Proc. Nutr. Soc."},{"key":"ref_11","doi-asserted-by":"crossref","unstructured":"Rogeri, P.S., Gasparini, S.O., Martins, G.L., Costa, L.K.F., Araujo, C.C., Lugaresi, R., Kopfler, M., and Lancha, A.H. (2020). Crosstalk Between Skeletal Muscle and Immune System: Which Roles Do IL-6 and Glutamine Play?. Front. Physiol., 11.","DOI":"10.3389\/fphys.2020.582258"},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"941","DOI":"10.1007\/s00421-020-04337-1","article-title":"A Focused Review of Myokines as a Potential Contributor to Muscle Hypertrophy from Resistance-Based Exercise","volume":"120","author":"Cornish","year":"2020","journal-title":"Eur. J. Appl. Physiol."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"111544","DOI":"10.1016\/j.exger.2021.111544","article-title":"Inflammation and Sarcopenia: A Focus on Circulating Inflammatory Cytokines","volume":"154","author":"Pan","year":"2021","journal-title":"Exp. Gerontol."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"101697","DOI":"10.1016\/j.arr.2022.101697","article-title":"The Hormetic and Hermetic Role of IL-6","volume":"80","author":"Forcina","year":"2022","journal-title":"Ageing Res. Rev."},{"key":"ref_15","first-page":"67","article-title":"Skeletal Muscle IL-4, IL-4Ralpha, IL-13 and IL-13Ralpha1 Expression and Response to Strength Training","volume":"13","author":"Prokopchuk","year":"2007","journal-title":"Exerc. Immunol. Rev."},{"key":"ref_16","doi-asserted-by":"crossref","unstructured":"Chen, D., Tang, T.-X., Deng, H., Yang, X.-P., and Tang, Z.-H. (2021). Interleukin-7 Biology and Its Effects on Immune Cells: Mediator of Generation, Differentiation, Survival, and Homeostasis. Front. Immunol., 12.","DOI":"10.3389\/fimmu.2021.747324"},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"457","DOI":"10.1038\/nrendo.2012.49","article-title":"Muscles, Exercise and Obesity: Skeletal Muscle as a Secretory Organ","volume":"8","author":"Pedersen","year":"2012","journal-title":"Nat. Rev. Endocrinol."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"273","DOI":"10.1038\/s41574-022-00641-2","article-title":"Exerkines in Health, Resilience and Disease","volume":"18","author":"Chow","year":"2022","journal-title":"Nat. Rev. Endocrinol."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"1360","DOI":"10.1038\/s41591-018-0131-6","article-title":"The Exerkine Apelin Reverses Age-Associated Sarcopenia","volume":"24","author":"Vinel","year":"2018","journal-title":"Nat. Med."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"108822","DOI":"10.1016\/j.intimp.2022.108822","article-title":"Apelin\/APJ System in Inflammation","volume":"109","author":"Wang","year":"2022","journal-title":"Int. Immunopharmacol."},{"key":"ref_21","first-page":"77","article-title":"Leukaemia Inhibitory Factor--an Exercise-Induced Myokine","volume":"16","author":"Broholm","year":"2010","journal-title":"Exerc. Immunol. Rev."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"45","DOI":"10.1007\/978-3-319-27511-6_3","article-title":"The Role of Leukemia Inhibitory Factor Receptor Signaling in Skeletal Muscle Growth, Injury and Disease","volume":"900","author":"Hunt","year":"2016","journal-title":"Adv. Exp. Med. Biol."},{"key":"ref_23","first-page":"189","article-title":"Leukemia Inhibitory Factor (LIF) and Its Biological Activity","volume":"59","author":"Chodorowska","year":"2004","journal-title":"Ann. Univ. Mariae Curie Sklodowska Med."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"17","DOI":"10.1186\/s12950-019-0221-3","article-title":"Deficiency of Fibroblast Growth Factor 21 Aggravates Obesity-Induced Atrophic Responses in Skeletal Muscle","volume":"16","author":"Kim","year":"2019","journal-title":"J. Inflamm."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"203","DOI":"10.1007\/s42978-022-00164-2","article-title":"Myokine Response to Blood-Flow Restricted Resistance Exercise in Younger and Older Males in an Untrained and Resistance-Trained State: A Pilot Study","volume":"5","author":"Cordingley","year":"2022","journal-title":"J. Sci. Sport Exerc."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"2018","DOI":"10.1016\/j.stemcr.2017.10.027","article-title":"Coupling between Myogenesis and Angiogenesis during Skeletal Muscle Regeneration Is Stimulated by Restorative Macrophages","volume":"9","author":"Latroche","year":"2017","journal-title":"Stem Cell Rep."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"C1437","DOI":"10.1152\/ajpcell.00427.2023","article-title":"Apelin Regulates Skeletal Muscle Adaptation to Exercise in a High-Intensity Interval Training Model","volume":"326","author":"Skarp","year":"2024","journal-title":"Am. J. Physiol.-Cell Physiol."},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"12997","DOI":"10.1038\/s41598-017-13479-w","article-title":"IL-15 Promotes Human Myogenesis and Mitigates the Detrimental Effects of TNF\u03b1 on Myotube Development","volume":"7","author":"Wallace","year":"2017","journal-title":"Sci. Rep."},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"845","DOI":"10.1016\/S1065-6995(03)00172-0","article-title":"Interleukin-15 Increases Myosin Accretion in Human Skeletal Myogenic Cultures","volume":"27","author":"Furmanczyk","year":"2003","journal-title":"Cell Biol. Int."},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"55","DOI":"10.1006\/excr.2002.5624","article-title":"Overexpression of Interleukin-15 Induces Skeletal Muscle Hypertrophy in Vitro: Implications for Treatment of Muscle Wasting Disorders","volume":"280","author":"Quinn","year":"2002","journal-title":"Exp. Cell Res."},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"463","DOI":"10.1038\/nature10777","article-title":"A PGC1-\u03b1-Dependent Myokine That Drives Brown-Fat-like Development of White Fat and Thermogenesis","volume":"481","author":"Wu","year":"2012","journal-title":"Nature"},{"key":"ref_32","first-page":"524","article-title":"The Effect of Exercise Interventions on Irisin Level: A Systematic Review and Meta-Analysis of Randomized Controlled Trials","volume":"21","author":"Hejazi","year":"2022","journal-title":"EXCLI J."},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"1289","DOI":"10.1210\/jc.2014-2932","article-title":"Serum Irisin Levels Are Regulated by Acute Strenuous Exercise","volume":"100","author":"Scheuermann","year":"2015","journal-title":"J. Clin. Endocrinol. Metab."},{"key":"ref_34","doi-asserted-by":"crossref","unstructured":"Miyamoto-Mikami, E., Sato, K., Kurihara, T., Hasegawa, N., Fujie, S., Fujita, S., Sanada, K., Hamaoka, T., Tabata, I., and Iemitsu, M. (2015). Endurance Training-Induced Increase in Circulating Irisin Levels Is Associated with Reduction of Abdominal Visceral Fat in Middle-Aged and Older Adults. PLoS ONE, 10.","DOI":"10.1371\/journal.pone.0120354"},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"1538","DOI":"10.1038\/ijo.2014.42","article-title":"Irisin Stimulates Muscle Growth-Related Genes and Regulates Adipocyte Differentiation and Metabolism in Humans","volume":"38","author":"Huh","year":"2014","journal-title":"Int. J. Obes."},{"key":"ref_36","doi-asserted-by":"crossref","unstructured":"Endo, Y., Nourmahnad, A., and Sinha, I. (2020). Optimizing Skeletal Muscle Anabolic Response to Resistance Training in Aging. Front. Physiol., 11.","DOI":"10.3389\/fphys.2020.00874"},{"key":"ref_37","doi-asserted-by":"crossref","first-page":"116","DOI":"10.1111\/sms.12901","article-title":"Skeletal Muscle IL-15\/IL-15R\u03b1 and Myofibrillar Protein Synthesis after Resistance Exercise","volume":"28","author":"McKendry","year":"2018","journal-title":"Scand. J. Med. Sci. Sports"},{"key":"ref_38","doi-asserted-by":"crossref","first-page":"106","DOI":"10.1016\/j.exger.2009.10.012","article-title":"Serum and Muscle Interleukin-15 Levels Decrease in Aging Mice: Correlation with Declines in Soluble Interleukin-15 Receptor Alpha Expression","volume":"45","author":"Quinn","year":"2010","journal-title":"Exp. Gerontol."},{"key":"ref_39","doi-asserted-by":"crossref","first-page":"3719","DOI":"10.1096\/fj.201700080R","article-title":"Nutritional Interventions and the IL-6 Response to Exercise","volume":"31","author":"Hennigar","year":"2017","journal-title":"FASEB J."},{"key":"ref_40","doi-asserted-by":"crossref","first-page":"e13766","DOI":"10.1111\/apha.13766","article-title":"Factors Mediating Exercise-induced Organ Crosstalk","volume":"234","author":"Sabaratnam","year":"2022","journal-title":"Acta Physiol."},{"key":"ref_41","doi-asserted-by":"crossref","unstructured":"Senesi, P., Luzi, L., and Terruzzi, I. (2020). Adipokines, Myokines, and Cardiokines: The Role of Nutritional Interventions. Int. J. Mol. Sci., 21.","DOI":"10.3390\/ijms21218372"},{"key":"ref_42","doi-asserted-by":"crossref","first-page":"503","DOI":"10.1007\/s40279-020-01388-4","article-title":"Sex Differences in Adaptations in Muscle Strength and Size Following Resistance Training in Older Adults: A Systematic Review and Meta-Analysis","volume":"51","author":"Jones","year":"2021","journal-title":"Sports Med."},{"key":"ref_43","doi-asserted-by":"crossref","first-page":"1448","DOI":"10.1519\/JSC.0000000000003521","article-title":"Sex Differences in Resistance Training: A Systematic Review and Meta-Analysis","volume":"34","author":"Roberts","year":"2020","journal-title":"J. Strength Cond. Res."},{"key":"ref_44","doi-asserted-by":"crossref","first-page":"87","DOI":"10.1016\/j.nutres.2018.09.005","article-title":"Omega-3 Supplementation with Resistance Training Does Not Improve Body Composition or Lower Biomarkers of Inflammation More so than Resistance Training Alone in Older Men","volume":"60","author":"Cornish","year":"2018","journal-title":"Nutr. Res."}],"container-title":["Muscles"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2813-0413\/3\/3\/18\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T15:08:30Z","timestamp":1760108910000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2813-0413\/3\/3\/18"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2024,7,1]]},"references-count":44,"journal-issue":{"issue":"3","published-online":{"date-parts":[[2024,9]]}},"alternative-id":["muscles3030018"],"URL":"https:\/\/doi.org\/10.3390\/muscles3030018","relation":{},"ISSN":["2813-0413"],"issn-type":[{"value":"2813-0413","type":"electronic"}],"subject":[],"published":{"date-parts":[[2024,7,1]]}}}