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

Abstract

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.