Accumulated oxygen deficit during exercise to exhaustion determined at different supramaximal work rates

The aim of the study was to determine the effect of supramaximal exercise intensity during constant work-rate cycling to exhaustion on the accumulated oxygen deficit (AOD) and to determine the test-retest reliability of AOD. Methods: Twenty-one trained male cyclists and triathletes (mean ± SD for age and maximal oxygen uptake [VO 2 max] were 41 ± 7 y and 4.53 ± 0.54 L/min, respectively) performed initial tests to determine the linear relationship between VO 2 and power output, and VO 2 max. In subsequent trials, AOD was determined from exhaustive square-wave cycling trials at 105%, 112.5% (in duplicate), 120%, and 127.5% VO 2 max. Results: Exercise intensity had an effect (P = .011) on the AOD (3.84 ± 1.11, 4.23 ± 0.96, 4.09 ± 0.87, and 3.93 ± 0.89 L at 105%, 112.5%, 120%, and 127.5% VO 2 max, respectively). Specifically, AOD at 112.5% VO 2 max was greater than at 105% VO 2 max (P = .033) and at 127.5% VO 2 max (P = .022), but there were no differences between the AOD at 112.5% and 120% VO 2 max. In 76% of the participants, the maximal AOD occurred at 112.5% or 120% VO 2 max. The reliability statistics of the AOD at 112.5% VO 2 max, determined as intraclass correlation coefficient and coefficient of variation, were .927 and 8.72%, respectively. Conclusions: The AOD, determined from square-wave cycling bouts to exhaustion, peaks at intensities of 112.5-120% VO 2 max. Moreover, the AOD at 112.5% VO 2 max exhibits an 8.72% test-retest reliability