How Different Respiratory Rate Patterns affect Cardiorespiratory Variables and Performance

This study aims to elucidate how respiratory rate (RR) patterns may affect respiratory gas exchange variables and performance during incremental intensity- exercise. 10 healthy young men (mean ± SD, age: 20.7 ± 0.5 years, height: 174.3 ± 5.7 cm, and body mass: 72.6 ± 10.4 kg) performed three incremental tests on a cycle ergometer at three different RR (60, 45 and 30 breaths per min) in each trial. During the tests, tidal volume (TV), minute ventilation (VE), fractional content of oxygen (FeO2), fractional content of carbon dioxide (FeCO2), oxygen uptake (VO2), expiratory carbon dioxide (VCO2), equivalent of oxygen (EqO2), VE/VCO2, and respiratory exchange ratio (RER) were determinate breath-by-breath. Additionally, exercise time (as a performance marker) was measured. Statistical analyses for the results were carried out to determine significant differences between the three trials. VCO2, VO2, and exercise time did not show statistical differences in the three trials. Therefore, we concluded that RR affects some respiratory gas exchange variables but does not influence the VO2max and endurance performance.