{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,12]],"date-time":"2026-08-12T14:38:44Z","timestamp":1786545524141,"version":"build-2736575974"},"reference-count":41,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2026,8,12]],"date-time":"2026-08-12T00:00:00Z","timestamp":1786492800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Physiol."],"abstract":"\n Background and study aim<\/jats:title>\n \n Combat sports involve repeated high-intensity efforts separated by short recovery periods, creating substantial demands on aerobic function and recovery. However, little is known about whether resting metabolic and redox-related biomarkers are associated with cardiorespiratory fitness in combat sport athletes. This pilot cross-sectional study examined the associations of resting plasma adenosine triphosphate (ATP), total antioxidant capacity (T-AOC), superoxide dismutase (SOD), malondialdehyde (MDA), and glutathione peroxidase (GPX) with maximal oxygen uptake (VO\n 2<\/jats:sub>\n max) and relative VO\n 2<\/jats:sub>\n max.\n <\/jats:p>\n <\/jats:sec>\n \n Materials and methods<\/jats:title>\n \n Resting venous blood samples were collected once after at least 8\u00a0h of fasting and before a graded treadmill exercise test; no post-exercise samples were obtained. Cardiorespiratory fitness was evaluated using a graded treadmill exercise test, with VO\n 2<\/jats:sub>\n max, relative VO\n 2<\/jats:sub>\n max, respiratory exchange ratio, exercise heart rate, and exercise duration recorded. Statistical analyses included descriptive statistics, Spearman and partial correlations, multiple linear regression, and decision tree modeling, with additional robustness checks using Bootstrap confidence intervals and permutation tests.\n <\/jats:p>\n <\/jats:sec>\n \n Results<\/jats:title>\n \n Twenty-one combat sport athletes were included. Mean VO\n 2<\/jats:sub>\n max was 2937.19 \u00b1 643.93 mL\/min, and mean relative VO\n 2<\/jats:sub>\n max was 42.38 \u00b1 8.80 mL\/kg\/min.s. T-AOC was strongly positively correlated with both VO\n 2<\/jats:sub>\n max (Spearman\u2019s \u03c1 = 0.723, p &lt; 0.01) and relative VO\n 2<\/jats:sub>\n max (Spearman\u2019s \u03c1 = 0.678, p &lt; 0.01), and these associations remained significant in partial correlation analyses adjusted for age, sex, height, and body mass. MDA was moderately correlated with relative VO\n 2<\/jats:sub>\n max (\u03c1 = 0.454, p &lt; 0.05). In multivariable models, T-AOC was the only biomarker significantly associated with VO\n 2<\/jats:sub>\n max and, together with MDA, was associated with relative VO\n 2<\/jats:sub>\n max. Partial correlation, decision tree, Bootstrap, and permutation analyses consistently supported T-AOC as the most stable signal across analytical approaches, suggesting that its association with cardiorespiratory fitness was not model-specific. By contrast, ATP, SOD, and GPX showed limited independent explanatory value.\n <\/jats:p>\n <\/jats:sec>\n \n Conclusions<\/jats:title>\n \n Combat sport athletes in this pilot sample demonstrated high cardiorespiratory fitness. In this pilot sample, resting T-AOC showed the most consistent positive association with VO\n 2<\/jats:sub>\n max and relative VO\n 2<\/jats:sub>\n max, while MDA showed an exploratory association with relative VO\n 2<\/jats:sub>\n max. Because biomarkers were measured once before exercise, these results represent baseline cross-sectional associations and do not establish causality, acute exercise responses, or recovery status. Larger longitudinal studies are needed to confirm these findings.\n <\/jats:p>\n <\/jats:sec>","DOI":"10.3389\/fphys.2026.1863045","type":"journal-article","created":{"date-parts":[[2026,8,12]],"date-time":"2026-08-12T13:42:41Z","timestamp":1786542161000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":0,"title":["Associations of resting plasma adenosine triphosphate, antioxidant capacity, and oxidative stress biomarkers with cardiorespiratory fitness in combat sport athletes: a pilot cross-sectional study"],"prefix":"10.3389","volume":"17","author":[{"given":"Jinling","family":"Huang","sequence":"first","affiliation":[{"name":"Department of Basic Teaching, Pujiang College, Nanjing University of Technology","place":["Nanjing, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"L\u00fcfeng","family":"Miao","sequence":"additional","affiliation":[{"name":"School of Sports Training, Nanjing Sport Institute","place":["Nanjing, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yangjun","family":"Liu","sequence":"additional","affiliation":[{"name":"School of Physical Education and Health, Chengdu University of Traditional Chinese Medicine","place":["Chengdu, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1965","published-online":{"date-parts":[[2026,8,12]]},"reference":[{"key":"B1","doi-asserted-by":"publisher","first-page":"1933","DOI":"10.1080\/02640414.2020.1776002","article-title":"Power, precision, and sample size estimation in sport and exercise science research","volume":"38","author":"Abt","year":"2020","journal-title":"J. Sports Sci."},{"key":"B2","doi-asserted-by":"publisher","first-page":"48","DOI":"10.1038\/s41526-024-00389-1","article-title":"Systematic review of the effectiveness of standalone passive countermeasures on microgravity-induced physiologic deconditioning","volume":"10","author":"Ahmed","year":"2024","journal-title":"NPJ Microgravity"},{"key":"B3","doi-asserted-by":"publisher","first-page":"269","DOI":"10.1002\/(SICI)1099-0844(1998120)16:4<269::AID-CBF797>3.0.CO;2-B","article-title":"Exercise, depletion of antioxidants and antioxidant manipulation","volume":"16","author":"Balakrishnan","year":"1998","journal-title":"Cell Biochem. Funct."},{"key":"B4","doi-asserted-by":"publisher","first-page":"63","DOI":"10.1186\/s40798-021-00345-3","article-title":"Profiling combat sports athletes: Competitive history and outcomes according to sports type and current level of competition","volume":"7","author":"Barley","year":"2021","journal-title":"Sports Med. - Open"},{"key":"B5","doi-asserted-by":"publisher","DOI":"10.3389\/fphys.2012.00142","article-title":"Effects of physical activity and inactivity on muscle fatigue","volume":"3","author":"Bogdanis","year":"2012","journal-title":"Front. Physiol."},{"key":"B6","doi-asserted-by":"publisher","first-page":"80","DOI":"10.3390\/sports10060080","article-title":"Exploratory systematic review of mixed martial arts: An overview of performance of importance factors with over 20,000 athletes","volume":"10","author":"Bueno","year":"2022","journal-title":"Sports (Basel)"},{"key":"B7","doi-asserted-by":"publisher","first-page":"241","DOI":"10.2147\/oajsm.s88265","article-title":"Do physiological measures predict selected CrossFit(\u00ae) benchmark performance","volume":"6","author":"Butcher","year":"2015","journal-title":"Open Access J. Sports Med."},{"key":"B8","doi-asserted-by":"publisher","first-page":"1935","DOI":"10.3390\/children9121935","article-title":"Predicting VO(2)max in children and adolescents aged between 6 and 17 using physiological characteristics and participation in sport activities: A cross-sectional study comparing different regression models stratified by gender","volume":"9","author":"Carayanni","year":"2022","journal-title":"Children (Basel)"},{"key":"B9","doi-asserted-by":"publisher","first-page":"649","DOI":"10.1007\/s11302-021-09816-4","article-title":"Purinergic signaling as a new mechanism underlying physical exercise benefits: a narrative review","volume":"17","author":"Cardoso","year":"2021","journal-title":"Purinergic Signal."},{"key":"B10","doi-asserted-by":"publisher","first-page":"350","DOI":"10.3390\/antiox11020350","article-title":"Effects of exercise training on the autonomic nervous system with a focus on anti-inflammatory and antioxidants effects","volume":"11","author":"Daniela","year":"2022","journal-title":"Antioxid. (Basel)"},{"key":"B11","doi-asserted-by":"publisher","first-page":"1877","DOI":"10.3390\/nu12061877","article-title":"Total dietary antioxidant intake including polyphenol content: Is it capable to fight against increased oxidants within the body of ultra-endurance athletes","volume":"12","author":"Devrim-Lanpir","year":"2020","journal-title":"Nutrients"},{"key":"B12","first-page":"1","article-title":"The impact of hand-to-hand combat exercises on physical health: a bibliometric and visualization analysis","volume":"21","author":"Dou","year":"2025","journal-title":"Arch. Budo-J. Innovative Agonology"},{"key":"B13","doi-asserted-by":"publisher","first-page":"2057","DOI":"10.1152\/physrev.00054.2021","article-title":"Molecular responses to acute exercise and their relevance for adaptations in skeletal muscle to exercise training","volume":"103","author":"Egan","year":"2023","journal-title":"Physiol. Rev."},{"key":"B14","doi-asserted-by":"publisher","first-page":"1","DOI":"10.1016\/j.freeradbiomed.2021.07.020","article-title":"Six weeks of high intensity cycle training reduces H(2)O(2) emission and increases antioxidant protein levels in obese adults with risk factors for type 2 diabetes","volume":"173","author":"Flensted-Jensen","year":"2021","journal-title":"Free Radic. Biol. Med."},{"key":"B15","doi-asserted-by":"publisher","first-page":"297","DOI":"10.3390\/metabo13020297","article-title":"Energy system contributions during Olympic combat sports: A narrative review","volume":"13","author":"Franchini","year":"2023","journal-title":"Metabolites"},{"key":"B16","doi-asserted-by":"publisher","first-page":"1693","DOI":"10.1152\/physrev.00017.2022","article-title":"The molecular athlete: exercise physiology from mechanisms to medals","volume":"103","author":"Furrer","year":"2023","journal-title":"Physiol. Rev."},{"key":"B17","doi-asserted-by":"publisher","DOI":"10.1096\/fj.202500554r","article-title":"Aerobic capacity beyond cardiorespiratory fitness linking mitochondrial function, disease resilience and healthy aging","volume":"39","author":"Gao","year":"2025","journal-title":"FASEB J."},{"key":"B18","first-page":"317","article-title":"Key considerations in the preparation of the elite athlete: Planning, performance, and recovery","volume-title":"Fundamentals of Recovery, Regeneration, and Adaptation to Exercise Stress: An Integrated Approach","author":"Guard","year":"2025"},{"key":"B19","first-page":"185","article-title":"Relationship between cardiorespiratory fitness, maximum oxygen consumption [Vo2max] and some hematological parameters in athletes in Port Harcourt","volume":"15","author":"Gwotmut","year":"2023","journal-title":"Unizik J. Educ. Res. Policy Stud."},{"key":"B20","doi-asserted-by":"publisher","DOI":"10.3389\/fspor.2022.793603","article-title":"Dwarfs on the shoulders of giants: Bayesian analysis with informative priors in elite sports research and decision making","volume":"4","author":"Hecksteden","year":"2022","journal-title":"Front. Sports Act. Living"},{"key":"B21","doi-asserted-by":"publisher","first-page":"1","DOI":"10.1007\/s42978-024-00297-6","article-title":"Dietary supplementation strategies for improving training adaptations, antioxidant status and performance of volleyball players: A systematic review","author":"Hern\u00e1ndez-Landa","year":"2024","journal-title":"J. Sci. Sport Exercise"},{"key":"B22","doi-asserted-by":"publisher","DOI":"10.18002\/rama.v16i1s.7000","article-title":"Developing aerobic power and capacity for combat sports athletes","volume":"16","author":"Julio","year":"2021","journal-title":"Rev. Artes Marciales Asi\u00e1ticas"},{"key":"B23","doi-asserted-by":"publisher","first-page":"88","DOI":"10.5114\/hm.2020.94194","article-title":"The pacing of mixed martial arts sparring bouts: a secondary investigation with new analyses of previous data to support accelerometry as a potential method of monitoring pacing","volume":"21","author":"Kirk","year":"2020","journal-title":"Hum. Mov."},{"key":"B24","doi-asserted-by":"publisher","first-page":"259","DOI":"10.1016\/j.scispo.2020.11.006","article-title":"Physiological determinants of VO2max and the methods to evaluate it: A critical review","volume":"36","author":"Lee","year":"2021","journal-title":"Sci. Sports"},{"key":"B25","doi-asserted-by":"publisher","DOI":"10.1016\/j.redox.2020.101471","article-title":"Antioxidant supplements and endurance exercise: current evidence and mechanistic insights","volume":"35","author":"Mason","year":"2020","journal-title":"Redox Biol."},{"key":"B26","volume-title":"Physical Tests, Hormonal and Oxidative-Stress Related Biomarkers in Intermittent Training of Taekwondo Athletes","author":"Mathunjwa","year":"2019"},{"key":"B27","doi-asserted-by":"publisher","DOI":"10.3390\/antiox13050573","article-title":"The impact of physical exercise on oxidative and nitrosative stress: balancing the benefits and risks","volume":"13","author":"Meng","year":"2024","journal-title":"Antioxid. (Basel)"},{"key":"B28","article-title":"Long-term regular exercise increases VO2max forcardiorespiratory fitness","volume-title":"Innovation in Science and Technology","author":"Mohajan","year":"2023"},{"key":"B29","doi-asserted-by":"publisher","DOI":"10.1155\/2023\/6014706","article-title":"Assessment of oxidative stress by the estimation of lipid peroxidation marker malondialdehyde (MDA) in patients with chronic periodontitis: A systematic review and meta-analysis","volume":"2023","author":"Mohideen","year":"2023","journal-title":"Int. J. Dent."},{"key":"B30","doi-asserted-by":"publisher","DOI":"10.1002\/fsn3.70714","article-title":"Phenolic compounds in exercise physiology: Dual role in oxidative stress and recovery adaptation","volume":"13","author":"\u00d6zdemir","year":"2025","journal-title":"Food Sci. Nutr."},{"key":"B31","doi-asserted-by":"publisher","DOI":"10.3390\/antiox12010039","article-title":"Exercise training and skeletal muscle antioxidant enzymes: an update","volume":"12","author":"Powers","year":"2023","journal-title":"Antioxid. (Basel)"},{"key":"B32","doi-asserted-by":"publisher","DOI":"10.1177\/22799036251407364","article-title":"Association between VO2max and antioxidant capacity in healthy young Saudi men","volume":"14","author":"Sayar","year":"2025","journal-title":"J. Public Health Res."},{"key":"B33","doi-asserted-by":"publisher","first-page":"921","DOI":"10.3390\/life14080921","article-title":"Effects of endurance training on antioxidant and hormonal status in peripheral blood of young healthy men","volume":"14","author":"Stojiljkovi\u0107","year":"2024","journal-title":"Life. (Basel)"},{"key":"B34","doi-asserted-by":"publisher","first-page":"2102","DOI":"10.3390\/molecules28052102","article-title":"The pleiotropic role of extracellular ATP in myocardial remodelling","volume":"28","author":"Sudi","year":"2023","journal-title":"Molecules"},{"key":"B35","doi-asserted-by":"publisher","DOI":"10.3389\/fphys.2020.610112","article-title":"Effect of running exercise on oxidative stress biomarkers: A systematic review","volume":"11","author":"Thirupathi","year":"2020","journal-title":"Front. Physiol."},{"key":"B36","doi-asserted-by":"publisher","DOI":"10.3389\/fphys.2025.1516268","article-title":"Supramaximal interval training using anaerobic speed reserve or sprint interval training in rowers","volume":"16","author":"Tongwu","year":"2025","journal-title":"Front. Physiol."},{"key":"B37","doi-asserted-by":"publisher","DOI":"10.3389\/fphys.2025.1620197","article-title":"Improving of 6 weeks of repeated sprint training on the aerobic and anaerobic power of college-age male rugby players","volume":"16","author":"Wang","year":"2025","journal-title":"Front. Physiol."},{"key":"B38","doi-asserted-by":"publisher","first-page":"91","DOI":"10.1016\/j.prrv.2009.04.002","article-title":"Assessment of physiological capacities of elite athletes & respiratory limitations to exercise performance","volume":"10","author":"Wells","year":"2009","journal-title":"Paediatr. Respir. Rev."},{"key":"B39","doi-asserted-by":"publisher","DOI":"10.3389\/fnut.2025.1618612","article-title":"The effects of exercise training and nutritional supplementation on taekwondo performance: a systematic review and meta-analysis","volume":"12","author":"Xu","year":"2025","journal-title":"Front. Nutr."},{"key":"B40","doi-asserted-by":"publisher","first-page":"22","DOI":"10.1007\/s00395-021-00859-7","article-title":"Adenosine and adenosine receptor-mediated action in coronary microcirculation","volume":"116","author":"Zhang","year":"2021","journal-title":"Basic Res. Cardiol."},{"key":"B41","doi-asserted-by":"publisher","first-page":"859","DOI":"10.1038\/s41419-024-07244-x","article-title":"Emerging mechanisms of lipid peroxidation in regulated cell death and its physiological implications","volume":"15","author":"Zheng","year":"2024","journal-title":"Cell Death Dis."}],"container-title":["Frontiers in Physiology"],"original-title":[],"link":[{"URL":"https:\/\/www.frontiersin.org\/articles\/10.3389\/fphys.2026.1863045\/full","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,8,12]],"date-time":"2026-08-12T13:42:43Z","timestamp":1786542163000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.frontiersin.org\/articles\/10.3389\/fphys.2026.1863045\/full"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,8,12]]},"references-count":41,"alternative-id":["10.3389\/fphys.2026.1863045"],"URL":"https:\/\/doi.org\/10.3389\/fphys.2026.1863045","relation":{},"ISSN":["1664-042X"],"issn-type":[{"value":"1664-042X","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,8,12]]},"article-number":"1863045"}}