Minimal Detectable Changes by the 2-Minute Marching Test for Easy Evaluation of Cardiorespiratory Response in Youth Following COVID-19 Infection

This study aims to evaluate the reliability and minimal detectable change (MDC) of the 2 min marching test (2MMT) for cardiovascular response, as well as to compare its outcomes with those of the 6 min walk test (6MWT), in youth recovering from post-COVID-19 condition. Forty-four youth with post-COVID-19 condition underwent two assessment sessions, separated by five days, utilizing both the 6MWT and 2MMT to measure cardiorespiratory response parameters. Test–retest reliability was found to be excellent for the 6MWT (ICC = 0.83; MDC95 = 8.06%) and good for the 2MMT (ICC = 0.78; MDC95 = 15.61%) between initial and follow-up measurements. The 2MMT demonstrates good reliability and validity for assessing cardiovascular response in youth with post-COVID-19 condition. The reported MDC values provide clinically meaningful thresholds that enable clinicians to distinguish true changes in performance from measurement error. These findings support the use of the 2MMT as a practical tool for clinical assessment, providing preliminary guidance for interpreting changes in performance. However, longitudinal monitoring of patient progress was not directly assessed in this study.