Effect of endurance versus resistance training on local muscle and systemic inflammation and oxidative stress in COPD

Limb muscle dysfunction in patients with COPD may be associated with local muscle and/or systemic inflammation, and therefore we investigated whether exercise training altered markers of inflammation and oxidative stress. We obtained vastus lateralis muscle biopsies and venous blood samples from patients with COPD (n = 30) before and after 8 weeks of resistance training (RT) (n = 15) or endurance training (ET) (n = 15). Healthy age‐matched subjects were included as baseline controls (n = 8). Inflammatory markers in muscle and systemically were determined by interleukins (IL), tumour necrosis factor alfa (TNF‐α), leukocyte concentration together with immunohistochemical staining for macrophages. Muscle oxidative stress and antioxidant capacity were determined by NADPH oxidase (NOX) and superoxide dismutase 2 (SOD2), respectively. Before exercise training, COPD patients had a higher muscular NOX protein content and circulating IL‐8, IL‐18, CRP, and leukocyte levels but a similar number of muscle‐infiltrating macrophages compared with controls. Eight weeks of ET or RT increased muscle SOD2 content with no difference between groups. Plasma TNF‐α, increased (P