Outdoor Endurance Training with Air Pollutant Exposure Versus Sedentary Lifestyle: A Comparison of Airway Immune Responses.

Although regular exercise-training improves immune/inflammatory status, the influence of air pollutants exposure during outdoor endurance training compared to a sedentary lifestyle has not yet been clarified. This study aimed to compare the immune/inflammatory responses in the airways of street runners and sedentary people after acute and chronic particulate matter (PM) exposure. Forty volunteers (street runners (RUN, n = 20); sedentary people (SED, n = 20)) were evaluated 1 (acute) and 10 (chronic) weeks after PM exposure. Cytokines [interferon (IFN)-γ, tumor necrosis factor (TNF)-α, interleukin (IL)-6, IL-10, IL-13, and IL-17A] in nasal lavage fluid, salivary antibacterial peptides (lactoferrin (LTF), cathelicidin (LL-37), defensin-α 1-3), and secretory immunoglobulin A (SIgA), plasma club cell protein (CC16), and fractional exhaled nitric oxide (FeNO) were analyzed. After acute exposure, the RUN group showed lower levels of IL-13, IL-10, and FeNO, but higher defensin-α than the SED group. After chronic exposure, the RUN group showed elevation of IFN-γ, IL-10, IL-17A, and a decrease of FeNO levels, whereas the SED group showed elevation of TNF-α, IL-6, IL-10, and a decrease of IL-13 levels. Comparing these groups, the RUN group showed higher levels of SIgA and LTF, and lower FeNO levels than the SED group. In relation to the Th immune response analysis after acute and chronic PM exposure, the RUN group showed a pattern associated with Th1, while in the SED group, a Th2 pattern was found. Both groups showed also a Th17 immune response pattern. Our results allow us to suggest that the immune/inflammatory status of the respiratory tract after acute and chronic PM exposure was improved by the long-standing regular practice of outdoor endurance exercise compared to a sedentary lifestyle.

Neuro-immuno-endocrine modulation in marathon runners.

OBJECTIVE: Sports practice alters the homeostasis of athletes. To achieve homeostatic equilibrium, the integrated action of the neuroendocrine and immune systems is necessary. Here we studied the relation between cytokines, hormones and mood states in marathon runners. METHODS: A total of 20 male recreational marathon runners (mean age = 35.7 ± 9 years) and 20 male sedentary individuals (mean age = 35.5 ± 7 years) were recruited. We compared the serum levels of growth hormone (GH), cortisol and interleukins 8 and 10 and the amounts of these two cytokines spontaneously produced by peripheral blood mononuclear cells. Blood samples of the sedentary group were collected at rest. Blood from the marathon runners was collected at rest (baseline: 24 h before the race), immediately after a marathon and 72 h after a marathon. Mood state analysis in both groups was performed using the 24-item Brunel Mood Scale (BRUMS). RESULTS: Our results showed that, at rest, levels of interleukins 8 and 10 in the supernatant of culture cells, the serum concentration of GH, and tension and vigour (evaluated using the BRUMS), were significantly higher in athletes compared to sedentary people. Immediately after the race all serum parameters analysed were statistically higher than baseline values. At 72 h after the marathon, serum levels of hormones and interleukins returned to values at rest, but the concentrations of interleukins in the supernatant of culture cells showed a significant reduction compared to values at rest. CONCLUSION: The higher serum levels of GH in athletes at rest and the higher production of cytokines in culture without previous stimulus suggest that marathon runners present mechanisms that may be associated with preparing the body to perform prolonged strenuous exercise, such as a marathon.