OBJECTIVES: Verify the metabolic, ventilatory, cardiovascular and perceived effort responses between the isotime two minute step test (2MST) and six minute step test (6MST) with two minute sit-to-stand test (STST) in individuals with COPD. MATERIALS AND METHODS:11 men with COPD (71 ± 8 years, FEV1 = 46.1 ± 15.2% predicted), clinically stable, were evaluation by STST and 6MST associated gas analysis and blood lactate in days which were not consecutive and not coincidental. In the 6MST and 2MST, the subjects were instructed ascend-to-descend a step 20 cm in height as quickly as possible. It was recommended that in the STST was performed in a chair 46 cm high. RESULTS: In the inter-tests analysis, there was no significant difference in the metabolic, ventilatory, cardiovascular variables and delta of variation (Δ) dyspnea at the peak of both tests, and 2MST. The Δheart frequency and Δfatigue in the lower limbs were significantly higher compared to STST for 2MST. We observed moderate and strong positive correlations between oxygen consumption, Δheart frequency and performances in 2MST and 6MST, between performances in 6MST and STST, and 2MST with STST. CONCLUSION: The tests showed metabolic, ventilatory, cardiovascular and dyspnoea responses similar; and 2MST, can be alternative to assess the functional limitations of individuals with COPD severe obstruction, providing a lower cardiovascular stress and muscle fatigue compared to the STST, the peripheral metabolic requirements and postural adjustments.
Chronic obstructive pulmonary disease; Exercise test; Exercise tolerance; Oxygen consumption; Muscle fatigue
