This study was undertaken to assess whether maximal O2 uptake (VO2max) can be used as an index of measuring aerobic capacity under the condition of increased respiratory resistance. Seven male subjects performed two incremental exercise tests on a cycle ergometer on different days: one control (C) and one breathing through an 8 mm bore diameter respiratory resistance (R). Ventilatory and gas exchange responses were measured with a turbine volume transducer and mass spectrometry, and processed breath-by-breath. VO2max was measured and anaerobic threshold (AT) was estimated non-invasively using the V-slope method. Maximal exercise performance was reduced significantly (by paired t-test, P

This study was undertaken to assess whether maximal O2 uptake (VO2max) can be used as an index of measuring aerobic capacity under the condition of increased respiratory resistance. Seven male subjects performed two incremental exercise tests on a cycle ergometer on different days: one control (C) and one breathing through an 8 mm bore diameter respiratory resistance (R). Ventilatory and gas exchange responses were measured with a turbine volume transducer and mass spectrometry, and processed breath-by-breath. VO2max was measured and anaerobic threshold (AT) was estimated non-invasively using the V-slope method. Maximal exercise performance was reduced significantly (by paired t-test, P