Cytokine Responses to Treadmill Running in Healthy and Illness-Prone Athletes

• Autores: Amanda Julie Cox, David B. Pyne, Philo U. Saunders, Robin Callister, Maree Gleeson
• Localización: Medicine & Science in Sports & exercise: Official Journal of the American College of Sports Medicine, ISSN 0195-9131, Vol. 39, Nº. 11, 2007, págs. 1918-1926
• Idioma: inglés
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• Dialnet Métricas: 1 Cita
• Resumen

  • Purpose: To characterize differences in cytokine responses to exercise of different intensities and durations between healthy and illness-prone runners.

    Methods: Trained distance runners were classified as healthy (no more than two episodes of upper-respiratory symptoms per year; N = 10) or illness-prone (four or more episodes per year; N = 8) and completed three treadmill tests: SHORT (30 min, 65% V[spacing dot above]O2max), LONG (60 min, 65% V[spacing dot above]O2max), and INTENSE (6 x 3 min, 90% V[spacing dot above]O2max). Blood samples were collected pre-, post-, 1 h, 10 h, and 24 h after exercise, and interleukin (IL)-2, IL-4, IL-6, IL-8, IL-10, IL-12, and IL-1ra concentrations were determined. Repeated-measures ANOVA was used to assess changes in cytokine responses to exercise. Magnitudes of changes and differences between groups were characterized using Cohen's effect size (ES) criteria.

    Results: Resting IL-8, IL-10, and IL-1ra concentrations were 19-38% lower (ES:0.38-0.96; small to moderate differences) in illness-prone runners. Similarly, postexercise IL-10 concentrations were 13-20% lower (ES: 0.20-0.37; small differences), and IL-1ra concentrations were 10-20% lower (ES: 0.22-0.38; small differences) in illness-prone subjects. In contrast, IL-6 elevations were 84-185% higher (ES: 0.29-0.59, small differences) in illness-prone subjects. Postexercise responses of IL-2, IL-4, and IL-12 were small and not substantially different between the groups.

    Conclusions: Cytokine responses to controlled treadmill running differ between healthy and illness-prone athletes. Illness-prone distance runners showed evidence suggestive of impaired inflammatory regulation in the hours after exercise that may account for the greater frequency of upper-respiratory symptoms experienced.