Our findings are pertinent to the very salient issue of the use of the 6MWT in clinical trials. Although the baseline 6MWT predicts outcomes, the change in the 6MWT distance does not.5 Therefore, the 6MWT has fallen into disfavor as a study end point. We hypothesized in our article that improving the 6MWT precision and reproducibility may be facilitated by maximizing the distance attained. Indeed, this concept is the foundation for our follow-up study (termed “the fast and the furious”), which is currently in the recruitment phase. Patients perform three 6MWTs on 2 separate days: (1) a standard 6MWT with the “far” instruction, (2) a 6MWT with the “fast” instruction, and (3) a 6MWT test with the fast instruction but a stronger (“furious”) menu of scripted instructions each minute to encourage more effort. The hypothesis being tested is that the greater the effort and distance, the less variability in subsequent 6MWTs. We can report that there is a trend supporting this hypothesis among the 12 patients studied thus far, as depicted in Table 1.