Assessment of peak oxygen uptake during handcycling: Test-retest reliability and comparison of a ramp-incremented and perceptually-regulated exercise test

Purpose: To examine the reliability of a perceptually-regulated maximal exercise test (PRETmax) to measure peak oxygen uptake (V˙O2peak) during handcycle exercise and to compare peak responses to those derived from a ramp-incremented protocol (RAMP). Methods: Twenty recreationally active individuals (14 male, 6 female) completed four trials across a 2-week period, using a randomised, counterbalanced design. Participants completed two RAMP protocols (20 W·min-1) in week 1, followed by two PRETmax in week 2, or vice versa. The PRETmax comprised five, 2-min stages clamped at Ratings of Perceived Exertion (RPE) 11, 13, 15, 17 and 20. Participants changed power output (PO) as often as required to maintain target RPE. Gas exchange variables (oxygen uptake, carbon dioxide production, minute ventilation), heart rate (HR) and PO were collected throughout. Differentiated RPE were collected at the end of each stage throughout trials. Results: For relative V˙O2peak, coefficient of variation (CV) was equal to 4.1% and 4.8%, with ICC(3,1) of 0.92 and 0.85 for repeated measures from PRETmax and RAMP, respectively. Measurement error was 0.15 L·min-1 and 2.11 ml·kg-1·min-1 in PRETmax and 0.16 L·min-1 and 2.29 ml·kg-1·min-1 during RAMP for determining absolute and relative V˙O2peak, respectively. The difference in V˙O2peak between PRETmax and RAMP was tending towards statistical significance (26.2 ± 5.1 versus 24.3 ± 4.0 ml·kg-1·min-1, P = 0.055). The 95% LoA were -1.9 ± 4.1 (-9.9 to 6.2) ml·kg-1·min-1. Conclusion: The PRETmax can be used as a reliable test to measure V˙O2peak during handcycle exercise in recreationally active participants. Whilst PRETmax tended towards significantly greater V˙O2peak values than RAMP, the difference is smaller than measurement error of determining V˙O2peak from PRETmax and RAMP.