title: Exercise Intensity and Recovery: Biomarkers of Injury, Inflammation, and Oxidative Stress.
abstract: Biomarkers of inflammation, muscle damage, and oxidative stress after high-intensity exercise have been described previously; however, further understanding of their role in the postexercise recovery period is necessary. Because these markers have been implicated in cell signaling, they may be specifically related to the training adaptations induced by high-intensity exercise. Thus, a clear model showing their responses to exercise may be useful in characterizing the relative recovery status of an athlete. The purpose of this study was twofold: (a) to investigate the time course of markers of muscle damage and inflammation in the blood from 3 to 72 hours after combined training exercises and (b) to investigate indicators of oxidative stress and damage associated with increased reactive oxygen species production during high-intensity exercise in elite athletes. Nineteen male athletes performed a combination of high-intensity aerobic and anaerobic training exercises. Samples were acquired immediately before and at 3, 6, 12, 24, 48, and 72 hours after exercise. The appearance and clearance of creatine kinase and lactate dehydrogenase in the blood occurred faster than previous studies have reported. The neutrophil/lymphocyte ratio summarizes the mobilization of 2 leukocyte subpopulations in a single marker and may be used to predict the end of the postexercise recovery period. Further analysis of the immune response using serum cytokines indicated that high-intensity exercise performed by highly trained athletes only generated inflammation that was localized to the skeletal muscle. Biomarkers are not a replacement for performance tests, but when used in conjunction, they may offer a better indication of metabolic recovery status. Therefore, the use of biomarkers can improve a coach's ability to assess the recovery period after an exercise session and to establish the intensity of subsequent training sessions.
authors.affiliation: 1Faculty of Physical Education, Federal University of Uberlandia (UFU), Uberlandia, Minas Gerais, Brazil; 2Laboratory of Biosciences of Human Motricity (LABIHM) of the Federal University of Rio de Janeiro State (UNIRIO), Rio de Janeiro, Brazil; 3Laboratory of Biochemistry and Molecular Biology, Institute of Genetics and Biochemistry, Federal University of Uberlandia (UFU), Uberlandia, Minas Gerais, Brazil; 4Laboratory of Immunobiology and Cellular Activation, Federal University of Trangulo Mineiro (UFTM), Uberaba, Minas Gerais, Brazil; 5Faculty of Kinesiology and Physical Education, University of Toronto, Toronto, Ontario, Canada; and 6Physiology and Experimental Medicine, The Hospital for Sick Children, Toronto, Canada.
authors.forename: Artur L
authors.initials: AL
authors.lastname: Bessa
authors.forename: Vanessa N
authors.initials: VN
authors.lastname: Oliveira
authors.forename: Guilherme G
authors.initials: GG
authors.lastname: Agostini
authors.forename: Renato J S
authors.initials: RJ
authors.lastname: Oliveira
authors.forename: Ana C S
authors.initials: AC
authors.lastname: Oliveira
authors.forename: Gillian E
authors.initials: GE
authors.lastname: White
authors.forename: Greg D
authors.initials: GD
authors.lastname: Wells
authors.forename: David N S
authors.initials: DN
authors.lastname: Teixeira
authors.forename: Foued S
authors.initials: FS
authors.lastname: Espindola
mesh_terms: D000328:Adult; D015415:Biomarkers / Q000378:metabolism; D002374:Catalase / Q000097:blood; D003402:Creatine Kinase / Q000097:blood; D016207:Cytokines / Q000097:blood; D015444:Exercise / Q000502:physiology*; D006801:Humans; D007770:L-Lactate Dehydrogenase / Q000097:blood; D007958:Leukocyte Count; D008297:Male; D009504:Neutrophils / Q000378:metabolism; D005082:Physical Exertion / Q000502:physiology*; D020127:Recovery of Function / Q000502:physiology
chemical_list: D015415:Biomarkers; D016207:Cytokines; D007770:L-Lactate Dehydrogenase; D002374:Catalase; D003402:Creatine Kinase