title: T helper cell cytokine profiles after endurance exercise.
abstract: Endurance exercise can cause immunosuppression and increase the risk of upper respiratory illness. The present study examined changes in the secretion of T helper (Th) cell cytokines after endurance exercise. Ten highly trained road cyclists [mean±SEM: age 24.2±1.7 years; height 1.82±0.02 m; body mass 73.8±2.0 kg; peak oxygen uptake 65.9±2.3 mL/(kg•min)] performed 2 h of cycling exercise at 90% of the second ventilatory threshold. Peripheral blood mononuclear cells were isolated and stimulated with phytohemagglutinin. Plasma cortisol concentrations and the concentration of Th1/Th2/Th17 cell cytokines were examined. Data were analyzed using both traditional statistics and magnitude-based inferences. Results revealed a significant decrease in plasma cortisol at 4-24 h postexercise compared with pre-exercise values. Qualitative analysis revealed postexercise changes in concentrations of plasma cortisol, IL-2, TNF, IL-4, IL-6, IL-10, and IL-17A compared with pre-exercise values. A Th1/Th2 shift was evident immediately postexercise. Furthermore, for multiple cytokines, including IL-2 and TNF (Th1), IL-6 and IL-10 (Th2), and IL-17 (Th17), no meaningful change in concentration occurred until more than 4 h postexercise, highlighting the duration of exercise-induced changes in immune function. These results demonstrate the importance of considering "clinically" significant versus statistically significant changes in immune cell function after exercise.
authors.affiliation: 1 Faculty of Health Sciences and Medicine, Bond University , Queensland, Australia .
authors.forename: Michael W
authors.initials: MW
authors.lastname: Kakanis
authors.forename: Jonathan
authors.initials: J
authors.lastname: Peake
authors.forename: Ekua W
authors.initials: EW
authors.lastname: Brenu
authors.forename: Michael
authors.initials: M
authors.lastname: Simmonds
authors.forename: Bon
authors.initials: B
authors.lastname: Gray
authors.forename: Sonya M
authors.initials: SM
authors.lastname: Marshall-Gradisnik
mesh_terms: D000328:Adult; D001642:Bicycling / Q000502:physiology; D015992:Body Mass Index; D016207:Cytokines / Q000097:blood / Q000276:immunology; D015444:Exercise / Q000502:physiology*; D006801:Humans; D006854:Hydrocortisone / Q000097:blood / Q000276:immunology; D007963:Leukocytes, Mononuclear / Q000276:immunology / Q000378:metabolism; D008297:Male; D010100:Oxygen / Q000378:metabolism; D010807:Physical Endurance / Q000276:immunology* / Q000502:physiology; D010835:Phytohemagglutinins / Q000276:immunology; D006377:T-Lymphocytes, Helper-Inducer / Q000276:immunology* / Q000378:metabolism; D014691:Ventilation; D055815:Young Adult
chemical_list: D016207:Cytokines; D010835:Phytohemagglutinins; D010100:Oxygen; D006854:Hydrocortisone