Translating Ramp V˙O2 into Constant Power Output: A Novel Strategy that Minds the Gap

INTRODUCTION: This study aimed to model the dissociation in the V˙O2/power output (PO) relationship between ramp incremental (RI) and constant work rate (CWR) exercise and to develop a novel strategy that resolves this gap and enables an accurate translation of the RI V˙O2 into a constant power output. METHODS: Nine young men completed two RI tests (30 and 15 W.min) and CWR tests at seven intensities across exercise intensity domains. The V˙O2/PO relationship for RI and CWR exercise was modelled and the dissociation was compared in terms of PO. The accuracy of three translation strategies was tested in the moderate (i.e., zone 1) and the heavy (i.e., zone 2) intensity domain. While strategy 1 comprised a simple mean response time (MRT) correction, strategy 2 and 3 accounted for the loss of mechanical efficiency in zone 2 by applying an extra correction that was based on, respectively, the difference between s2 - CWR and s2 - ramp or the ratio s2/s1. RESULTS: For all intensities, differences in PO were found between CWR and RI exercise (P<0.001). Overall, these differences were smaller for the 15 W.min compared to the 30 W.min protocol (P=0.012). Strategy 1 was accurate for PO selection in zone 1 (bias = 0.4±7.3W), but not in zone 2 (bias = 17.1±15.9W). Only strategy 2 was found to be accurate for both intensity zones (bias = 2.2±14.2W) (P=0.107). CONCLUSION: This study confirmed that a simple MRT correction works for PO selection in the moderate, but not in the heavy intensity domain. A novel strategy was tested and validated to accurately prescribe a constant PO based on the RI V˙O2 response in a population of young healthy men.