A Comparison of Methods to Identify the Mean Response Time of Ramp-Incremental Exercise for Exercise Prescription
Abstract
Introduction: The oxygen uptake (V̇O2) vs power output (PO) relationship from ramp incremental exercise (RAMP) is used to prescribe aerobic exercise. As PO increases, there is a delay in V̇O2 that contributes to a misalignment of V̇O2 from PO making precise prescription of exercise PO untenable. Three methods of determining Mean Response Time (exponential modeling (MRTEXP), linear modeling (MRTLIN), and the steady-state method (MRTSS)) were compared and evaluated for their accuracy at predicting the V̇O2 associated with two PO below estimated lactate threshold (qLT) and one above. Methods: Ten men performed a 30W·min−1 RAMP and three-30 min constant PO cycle ergometer trials at the aforementioned intensities. The measured steady-state V̇O2 was compared to the V̇O2 predicted after adjustment by each of the three MRTs. Results: For all three MRT methods, predicted V̇O2 was not different(P=1.000) from the measured, below qLT. Conclusion: All model predictions can be used for accurate exercise prescription provided the intensity is below qLT.