ABSTRACT Objective: To determine the responsiveness of the domain climbing up and going down stairs of the Functional Evaluation Scale for Duchenne Muscular Dystrophy (FES-DMD-D3) in a one-year follow-up study. Method: The study included 26 patients with DMD. Effect Size (ES) and Standardized Response Mean (SRM) described the scale’s responsiveness. Results: For climbing up stairs, ES showed that responsiveness was low in the three-month assessments (0.26; 0.35; 0.13; 0.17), low to moderate in the six-month assessments (0.58; 0.48; 0.33), moderate in the nine-month assessments (0.70; 0.68), and high in the 12-month assessment (0.88). SRM showed that responsiveness was low in the three-month assessments (0.29; 0.38; 0.18; and 0.19), low to moderate in the six-month assessments (0.59; 0.51; 0.36), moderate in the nine-month assessments (0.74 and 0.70), and high in the 12-month assessment (0.89). For going down stairs, ES showed that responsiveness was low in the three- and six-month assessments (0.16; 0.25; 0.09; 0.08 and 0.48; 0.35; 0.18, respectively), low to moderate in the nine-month assessments (0.59; 0.44), and moderate in the 12-month assessment (0.71). SRM showed that responsiveness was low in the three- and six-month assessments (0.25; 0.35; 0.12; 0.09 and 0.47; 0.38; 0.21, respectively), low to moderate in the nine-month assessment (0.62; 0.49), and moderate in the 12-month assessment (0.74). Conclusion: Climbing up stairs should be assessed at intervals of nine months or longer, when responsiveness is moderate to high. Going down stairs should be assessed annually because moderate responsiveness was observed in this period.