Intensity and duration of exercise on inflammatory markers and oxidative stress in patients with heart failure

Background: Inflammatory and oxidative adjustment related to exercise in chronic heart failure (CHF) depends on the exercise protocol. Aims: To compare the effects of 3 exercises of different intensities and durations on the inflammatory markers (soluble tumor necrosis factor receptor-sTNFR1 and interleukin-6-IL6) and on the oxidative stress (malondialdehyde-MDA and antioxidant enzyme catalase-CAT). Methods: After approval by the Ethics Committee of Research, 18 CHF patients performed 3 exercise sessions: moderate intensity for 30 minutes (M30); mild intensity for 30 minutes (L30), and mild intensity for 45 minutes (L45) (M30 isocaloric). Blood analysis was performed before exercise (BASELINE), immediately after (AFTER), and 1 hour after the end of each session (1H AFTER). Statistical analysis: The differences in the plasma levels were assessed by Friedman9s and Wilcoxon9s tests; the significance level was p Results: Acute M30 elevated sTNFR1 and MDA levels AFTER exercise (787.69±633.30 vs 842.88±558.75; p=0.039 and 2.07±1.54 vs 2.30±1.92; p=0.001, respectively) and CAT levels 1H AFTER (12.93±4.92 vs 13.86±3.77; p=0.049). L30 only increased IL6 levels AFTER exercise (1.53±0.58 vs 2.19±2.05; p=0.010) without changes in sTNFR1, MDA and CAT levels. Finally, in L45, only MDA levels increased AFTER exercise (2.30±1.78 vs 3.16±4.72; p=0.010). Conclusions: The exercise intensity was a stronger determinant of physiologic adjustments than was duration. Funding: Coord. de Aperfeicoamento de Pessoal de Nivel Superior (CAPES); Fundacao de Amparo a Pesquisa de Minas Gerais (FAPEMIG); Conselho Nacional de Desenvolvimento Cientifico e Tecnologico (CNPq); from Brazil.