Anti-inflammatory response to acute exercise is related with intensity and physical fitness

Purpose: The relationship between inflammatory markers and energetic metabolism has been explored. However, the relation between exercise intensity and fitness-status is unclear and it is necessary to understand this relationship to apply specific exercise guidance. The purpose of the study was to analyze metabolic and inflammatory responses imposed by acute exercise sessions performed at moderate, heavy and severe intensities and their relationship with physical fitnessstatus. Methods: Nineteen healthy male volunteers performed three acute exercise sessions until exhaustion or up to 60 minutes on a cycle ergometer at moderate (90% of VT1), heavy (midpoint between VT1/VT2), and severe (midpoint between VT2/Wmax) intensities. Blood lactate, glucose, NEFA, endotoxin and cytokines were determined for each exercise session. Peripheral and LPS-stimulated release of TNF-α, IL-6 and IL-10 were analyzed pre, post and 60-min after sessions. Results: In peripheral blood, severe intensity increased lactate, endotoxin and TNF-α immediately post-exercise and glucose at 60-min post-exercise. There was a trend for IL-10 increase at 60-min post-exercise in peripheral blood. Immediately post-exercise, LPS-stimulated TNF-α, IL-6, IL-6/IL-10 ratio and lactate levels were higher in the severe intensity while NEFA levels decreased at this time. At 60-min post-exercise higher concentrations of glucose and a trend for increased IL-10 were observed in severe intensity. Positive correlation was observed between maximal aerobic power and IL-10 (r=0.513, p=0.042) and negative correlations between maximal aerobic power and endotoxin (r=-0.531, p=0.034) and lactate (r=-0.538, p=0.031) in heavy intensity. Conclusion: Our data show a novel finding that higher cytokine responses occur at higher intensities, mainly in severe intensity. However, the anti-inflammatory (IL-10) response was physical fitness-dependent.