The 6MST is valid to estimate endurance training workload: A cross validation study.

<bold>Background:</bold> The six-minute stepper test (6MST) has been suggested to estimate endurance training intensity in people with COPD, but it lacks validation in an independent cohort. <bold>Aim:</bold> To assess how accurate are predictive equations using the 6MST in determining endurance training intensity based on cardiopulmonary exercise testing (CPET). <bold>Method:</bold> We used individual participant data from two prior studies (Grosbois et al., Int J COPD, 2016; Bonnevie et al., COPD, 2017). Endurance training intensity prescription from CPET, including heart rate at the ventilatory threshold (HRvt), the corresponding workload (Wvt), and a workload equivalent to 60% of peak workload (Wpeak), were compared with estimations derived from the 6MST using predictive equations (see abstract 46525). The comparison was performed using mean absolute difference (MAD) and a Bland-Altman analysis. <bold>Results:</bold> Eighty-six participants with COPD constituted the validation group. They were aged 60 (SD 8) years, weighted 75 (SD 19) kg and had moderate obstruction (FEV1: 53 (SD18) %). The MAD between prescriptions was 10 bpm (95% 8 to 12) for HRvt, 12 watts (95% CI 9 to 14) for Wvt and 10 watts (95% CI 8 to 12) for 60% Wpeak. Bland-Altman plots are shown in Figure 1. <bold>Conclusion:</bold> The 6MST is valid in prescribing initial workload endurance training intensity. Due to individual variation, the intensity should then be refined based on perceived exertion <fig><object-id>erj;64/suppl_68/PA601/F1</object-id><object-id>F1</object-id><object-id>F1</object-id><graphic></graphic></fig>.