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AIM We hypothesize that training-induced changes in muscle oxygen saturation (StO2 ) assessed by near-infrared spectroscopy (NIRS) during constant work rate cycling exercise (CWRE) may be a useful marker of the effects of training at 'vastus medialis' of the quadriceps in patients with chronic obstructive pulmonary disease (COPD). METHODS Incremental exercise [peak oxygen uptake (VO2 )] and CWRE at 70% pretraining peak VO2 , before and after 8-w training, were done in 10 healthy age-matched subjects (H) [80% men, 65(11) years, FEV1 105(14)%] and 16 COPD patients [94% men, 70(5) years, FEV1 46(11) %] encompassing the entire spectrum of disease severity, recruited in the outpatient clinics. NIRS was used to assess StO2 in the 'vastus medialis' of the left quadriceps. RESULTS Pretraining CWRE decreased StO2 (P

Background and objective Non-anaemic iron deficiency (NAID) might alter the oxygen pathway in health and disease. The current study aims at assessing the impact of NAID on aerobic capacity in patients with chronic obstructive pulmonary disease (COPD). Methods A prospective sample of 70 non-anaemic COPD patients candidate to participate in an 8-week pulmonary rehabilitation (PR) programme was studied. Incremental cycling exercise to peak oxygen uptake (V'O2peak) and constant work-rate exercise at 80% V'O2peak to exhaustion were assessed pre- and post-PR. Training-induced increase of endurance time (ET) ≥33%, which represented the minimal clinically important difference, classified patients as responders to exercise training. Results The prevalence of NAID was 48% (n = 34) showing no relationship with the Global Initiative for Chronic Obstructive Lung Disease stages (P = 0.209). Patients with NAID showed lower pre-training ET (P = 0.033) and V'O2peak (P = 0.007) than normal iron status (NIS) patients after adjustment for potential covariates. Significant training-induced physiological changes were seen in the NIS group (ΔV'O2peak 68(132) mL/min; P = 0.009), but not in the NAID group (ΔV'O2peak 26 (126) mL/min; P = 0.269). The NAID group showed lower percentage of responders to training (56%) than the NIS group (78%) (P = 0.041). Conclusions COPD patients with NAID showed lower pre-training aerobic capacity and reduced training-induced response than NIS patients after adjusting for potential confounding variables.

Background and Aim Both interval (IT) and continuous (CT) exercise training results in an improvement of aerobic capacity in patients with chronic obstructive pulmonary disease (COPD); however, their effects on cardiac autonomic function remains unclear. The aim of our study was to evaluate the effect of a supervised CT vs IT on autonomic cardiac function in COPD patients. Methods COPD patients were divided into two different groups according to training modality (IT or CT). Autonomic cardiac dysfunction (ACD) was defined as a heart rate recovery lower than 12 bpm heart rate after the first minute of maximal exercise (HRR1) and an abnormal chronotropic response (CR) to exercise (