Related Experiment Video
Updated: Mar 19, 2026

Supramaximal Intensity Hypoxic Exercise and Vascular Function Assessment in Mice
Published on: March 15, 2019
Accumulated Oxygen Deficit During Exercise to Exhaustion Determined at Different Supramaximal Work Rates
Purpose:
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 [V̇O2max] were 41 ± 7 y and 4.53 ± 0.54 L/min, respectively) performed initial tests to determine the linear relationship between V̇O2 and power output, and V̇O2max. In subsequent trials, AOD was determined from exhaustive square-wave cycling trials at 105%, 112.5% (in duplicate), 120%, and 127.5% V̇O2max.
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% V̇O2max, respectively). Specifically, AOD at 112.5% V̇O2max was greater than at 105% V̇O2max (P = .033) and at 127.5% V̇O2max (P = .022), but there were no differences between the AOD at 112.5% and 120% V̇O2max. In 76% of the participants, the maximal AOD occurred at 112.5% or 120% V̇O2max. The reliability statistics of the AOD at 112.5% V̇O2max, 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% V̇O2max. Moreover, the AOD at 112.5% V̇O2max exhibits an 8.72% test-retest reliability.
Related Concept Videos
Muscle Recovery and Fatigue
Exercise and Cardiac Output
Sustained exercise increases the muscles' oxygen demand, which can be...
Acute Respiratory Failure-II
The underlying physiological abnormalities that contribute to hypoxemic respiratory failure include:
Oxygen Transport in the Blood
Exercise and Cardiovascular Response
Light to moderate physical activity initiates a series of interconnected responses in the body. The heart rate modestly increases in anticipation of the workout, followed by widespread vasodilation as oxygen consumption by skeletal muscles increases. This results in decreased peripheral resistance, increased capillary blood flow, and accelerated...
Special considerations while measuring oxygen saturation
Ensuring accuracy in vital sign recordings while prioritizing patient comfort and minimizing anxiety is...

