Figure 4.

Change in FEV₁ % of predicted value (A), and FVC % of predicted value (B) from the baseline (time 0) and at 1 and 2 h after the start of the walk in Oxford Street or Hyde Park followed by measurements performed back in the laboratory at times indicated after the start of the walk for healthy volunteers and participants with COPD or IHD

Data are percentage changes (95% CI). COPD=chronic obstructive pulmonary disease. IHD=ischaemic heart disease. FEV₁=forced expiratory volume in the first second. FVC=forced vital capacity. *p<0·05, **p<0·01, ***p<0·001, comparing Oxford Street with Hyde Park. +p<0·05, ++p<0·01, +++p<0·001, compared with timepoint 0.