Exercise training in COPD: muscle O₂ transport plasticity

Both convective oxygen (O 2 ) transport to, and diffusive within, skeletal muscle are markedly diminished in patients with COPD. However, it is unknown how these determinants of peak O uptake ( V ′ mO respond to exercise training Therefore, the purpose this study was assess plasticity Adaptations 8 weeks single-leg knee-extensor were measured eight severe COPD (mean± sem forced expiratory volume 1 s (FEV 0.9±0.1 L) healthy, well-matched controls. Femoral arterial venous blood samples, thermodilution-assessed leg flow used determine utilisation at maximal pre- post-training. Training increased both (by ∼26% from 271±29 342±35 mL·min −1 controls ∼32% 418±37 553±41 ), restoring only ∼80% pre-training control . Muscle similarly ∼38% 6.6±0.9 9.1±0.9 ·mmHg ∼36% 10.4±0.7 14.1±0.8 reaching ∼90% values. In contrast, significantly 688±57 865±69 leaving (438±45 versus 491±51 ∼70% While largely restored by training, remained constrained limited transport.