Cautions with the use of data from incremental work‐rate tests for the prescription of work rates for interval training

Abstract

Ventilation per minute (VE) and percent fractional expired oxygen [FEO2(%)] data were used to determine the work rate at which the ventilatory threshold occurred during an incremental kayak test. Although an exponential curve fitted the ventilation data significantly, a quartic curve was more useful for subjective determination of the ventilatory threshold. A cubic polynomial curve fitted the blood lactate, pH, carbon dioxide pressure, bicarbonate, and base‐excess data from an incremental test on a treadmill, indicating the more complex curvilinear nature of these parameters as exercise intensity increased. This creates difficulties for the objective determination of a training intensity, which is likely to induce optimal training adaptation. In addition, the prescription of training based on a set blood lactate concentration may result in different physiologic stress for different individuals. Heart rate was found to vary little within a range of work rates that induced maximum variation in lactate conce...