Fig. 4

Secondary outcomes. A Showed the S_pO₂ at the beginning of the 6MWT at baseline (T0) and two months later (T1) in the intervention group (solid circles) or control group (solid squares). B Showed the minimal S_pO₂ during the 6MWT at baseline (T0) and two months later (T1) in the intervention group (solid circles) or control group (solid squares). C Showed the S_pO₂ at the end of the 6MWT at baseline (T0) and two months later (T1) in the intervention group (solid circles) or control group (solid squares). D Showed the FEV₁/FVC at baseline (T0) and two months later (T1) in the intervention group (solid circles) or control group (solid squares). E Showed the MVV at baseline (T0) and two months later (T1) in the intervention group (solid circles) or control group (solid squares). F Showed the mMRC score at baseline (T0) and two months later (T1) in the intervention group (solid circles) or control group (solid squares). T0 refers to the time when subjects were enrolled. T1 refers to the time when subjects were followed up at 2 months after enrollment. (*: P < 0.05; **: P < 0.001)