The Reliability of a Single-Trial Measurement of Maximal Accumulated Oxygen Deficit Determined via Perceptually-Regulated Exercise.

Purpose: The aim of this study was to evaluate the reliability of a single-trial determination of maximal accumulated oxygen deficit (MAOD) achieved via the aid of perceptually-regulated incremental exercise. Methods: 14 trained male cyclists (age: 45 ± 8 yrs; height: 1.82 ± 0.06 m; mass: 79.7 ± 6.7 kg; $${\dot{\rm{V}}{\rm{O}}_{2{\rm{max}}}}$$ V ˙ O 2 max : 4.09 ± 0.57 L·min−1) performed three trials of a submaximal incremental cycling test followed by a test to exhaustion at 116% of predicted $${\dot{\rm{V}}{\rm{O}}_{2{\rm{max}}}}$$ V ˙ O 2 max . The intensity for each stage of the incremental test was regulated by participants to elicit perceived exertion levels of 9–15 on the Borg (6–20) scale. Linear regression was used to estimate $${\dot{\rm{V}}{\rm{O}}_{2{\rm{max}}}}$$ V ˙ O 2 max at a perceived exertion level of 19. MAOD was calculated from the difference between predicted and actual oxygen demand in the test to exhaustion, reported in oxygen equivalents (O2 eq). A separate incremental test was used to measure $${\dot{\rm{V}}{\rm{O}}_{2{\rm{max}}}}$$ V ˙ O 2 max directly. Results: Correlation coefficients between perceived exertion and $${\dot{\rm{V}}{\rm{O}}_{2}}$$ V ˙ O 2 across trials were strong (r ≥0.99), and there were no between-trial differences in predicted $${\dot{\rm{V}}{\rm{O}}_{2{\rm{max}}}}$$ V ˙ O 2 max (4.03 ± 1.04, 3.76 ± 0.53, and 3.69 ± 0.64 L·min−1, respectively; p =.142) or MAOD (2.75 ± 2.28, 2.50 ± 1.53, and 2.93 ± 1.40 L O2 eq, respectively; p =.633). Nevertheless, the coefficients of variation for predicted $${\dot{\rm{V}}{\rm{O}}_{2{\rm{max}}}}$$ V ˙ O 2 max (14.2%) and MAOD (142.8%) were poor. Conclusions: The prediction of $${\dot{\rm{V}}{\rm{O}}_{2{\rm{max}}}}$$ V ˙ O 2 max from perceptually-regulated exercise displays a level of test-retest reliability which prevents its use as a means of evaluating MAOD reliably in a single-trial. [ABSTRACT FROM AUTHOR]