The VO<sub>2-</sub>power regression and estimated total energy demand for a 6-minute supramaximal exercise test was predicted from a continuous incremental exercise test. Sub-maximal VO<sub>2-</sub> power co-ordinates were established from the last 40 seconds(s) of 150-second exercise stages. The precision of the estimated total energy demand was determined using the 95% confidence interval (95% CI) of the estimated total energy demand. The linearity of the individual VO<sub>2-</sub>power regression equations was determined using Pearson's correlation coefficient. The mean 95% CI of the estimated total energy demand was 5.9±2.5 mL O<sub>2</sub> Eq•<sup>-1</sup>kg•min<sup>-1</sup>, and the mean correlation coefficient was 0.9942±0.0042. The current study contends that the sub-maximal VO<sub>2-</sub>power co-ordinates from a continuous incremental exercise test can be used to estimate supra-maximal energy demand without compromising the precision of the accumulated oxygen deficit (AOD) method.