Background:Step test (StT) has been used to assess exercise capacity in chronic pulmonary diseases. StT has been performed either paced (fixed rate) or self−paced cadence. However, an incremental step test (IStT) has never been validated in patients with COPD. Aim: To analyse the reproducibility of IStT in patients with COPD on different days and to test the validity of IstT as a maximal test comparing it to a symptom−limited incremental (ramp) cycle ergometry (CE) performed at the same day. Material and methods: Twelve patients with COPD (VEF1 53.3 ± 16.4 % pred) were submitted to two IStT (IStT−1 and IStT−2, height of 20 cm) and one CE. For IStT, it was used an auditive signal obtained from a CD with an initial cadence of 10 steps/min which was incremented in one step each 30 seconds. Results: No differences were observed among CE, IStT−1 and IStT−2 in the peak: VO2 (1098.6 ± 282.4 mL, 1162.8 ± 319.9 mL, 1201.0 ± 337.7 mL, respectively), VE (41.7 ± 14.5 L/min, 40.7 ± 14.2 L/min, 41.7 ± 14.4 L/min, respectively), VE/VVM (83.5 ± 81.3%, 81.3 ± 14.0 %; 81.5 ± 13.8%, respectively), and HR/HRpred (90.8 ± 14.16 bpm, 93.1 ± 13.3 bpm, 91.8 ± 10.6 bpm, respectively). Despite no significant difference in desaturation among tests, five patients presented with ∆ rest−exercise SpO2 ≥ 4% only in response to IStT. Both IStT showed to be highly reproducible for VO2 peak (Intraclass coefficient correlation − ICC: 0.98, p < 0.05) and number of steps (ICC: 0.95, p < 0.05) . There was a significant correlation between the number of steps climbed and VO2 peak (r = 0,77). Conclusion: A symptom−limited incremental step test, externally paced, does elicit maximal cardiopulmonary and metabolic responses similar to those observed during CE, beeing tolerable and reproducible in patients with COPD. This abstract is funded by: FAPIC−UNINOVE and FAPESP.