Fig. 1

Bland-Altman plots for %VO₂R and %HRR in treadmill exercise testing and 6-min walk test. a, d: %VO₂R vs. %HRR_sitting; b, e: %VO₂R vs. %HRR_lying; c, f: %VO₂R vs. %HRR_sleeping. Dotted lines represent the average differences between the two methods. Dashed lines represent 95% confidence intervals. Shaded areas represent 95% confidence intervals for mean and limits of agreement. VO₂R, oxygen consumption reserve; %HRR, percent heart rate reserve; %HRR_sitting, %HRR calculated with the HR while sitting; %HRR_lying, %HRR calculated with the HR while lying; awake; %HRR_sleeping = %HRR calculated using HR during sleep