Influence of pedal cadence on the respiratory compensation point and its relation to critical power

- V˙O2 associated with RCP was not significant different between 60 and 100 rpm.
- Neither work rates nor V˙O2 at RCP and CP were different across or within rpm.
- There was no relationship between work rates or V˙O2 values at RCP compared to CP.
- TRCP is more appropriately determined as a metabolic rate than a work rate.
- RCP and CP are not synonymous despite often occurring at similar intensities.

It is not known if the respiratory compensation point (RCP) is a distinct work rate (Watts (W)) or metabolic rate (V˙O2) and if the RCP is mechanistically related to critical power (CP). To examine these relationships, 10 collegiate men athletes performed cycling incremental and constant-power tests at 60 and 100 rpm to determine RCP and CP. RCP work rate was significantly (p ≤ 0.05) lower for 100 than 60 rpm (197 ± 24 W vs. 222 ± 24 W), while RCP V˙O2 was not significantly different (3.00 ± 0.33 l min−1 vs. 3.12 ± 0.41 l min−1). CP at 60 rpm (214 ± 51 W; V˙O2: 3.01 ± 0.69 l min−1) and 100 rpm (196 ± 46 W; V˙O2: 2.95 ± 0.54 l min−1) were not significantly different from RCP. However, RCP and CP were not significantly correlated. These findings demonstrate that RCP represents a distinct metabolic rate, which can be achieved at different power outputs, but that RCP and CP are not equivalent parameters and should not, therefore, be used synonymously.