Increased interleukin-6 is associated with low cardiorespiratory fitness in healthy people

To determine the relationship of maximal oxygen consumption as a cardiorespiratory marker with systemic inflammation. We measured fasting serum interleukin-6 (IL-6) and Tumor necrosis factor-α (TNF-α) and cardiorespiratory fitness (VO2max) in forty one healthy sedentary adult men (aged; 38 ± 4 year, BMI: 32 ± 6.14 kg/m2). The bivariate association between VO2max with IL-6 and TNF-α was examined with the Spearman rank correlation analysis. Serum IL-6 levels significantly negatively correlated VO2max (p = 0.009). A borderline signigcant negative association was observed between VO2max and TNF-α (p = 0.054). Based on this data, it was concluded that cardiorespiratory fitness may be predictor of systemic inflammation.