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The potential to change pacing and performance during 4000-m cycling time trials using hyperoxia and inspired gas-content deception
Davies, Michael J. Clark, Bradley Garvican-Lewis, Laura A. Welvaert, Marijke Gore, Christopher J. Thompson, Kevin G.
Davies, Michael J.
Clark, Bradley
Garvican-Lewis, Laura A.
Welvaert, Marijke
Gore, Christopher J.
Thompson, Kevin G.
Abstract
Purpose: To determine if a series of trials with fraction of inspired oxygen (FiO2) content deception could improve 4000-m cycling time-trial (TT) performance. Methods: A total of 15 trained male cyclists (mean [SD] body mass 74.2 [8.0] kg, peak oxygen uptake 62 [6] mL·kg−1·min−1) completed six 4000-m cycling TTs in a semirandomized order. After a familiarization TT, cyclists were informed in 2 initial trials they were inspiring normoxic air (NORM, FiO2 0.21); however, in 1 trial (deception condition), they inspired hyperoxic air (NORM-DEC, FiO2 0.36). During 2 subsequent TTs, cyclists were informed they were inspiring hyperoxic air (HYPER, FiO2 0.36), but in 1 trial, normoxic air was inspired (HYPER-DEC). In the final TT (NORM-INFORM), the deception was revealed and cyclists were asked to reproduce their best TT performance while inspiring normoxic air. Results: Greater power output and faster performances occurred when cyclists inspired hyperoxic air in both truthful (HYPER) and deceptive (NORM-DEC) trials than NORM (P < .001). However, performance only improved in NORM-INFORM (377 W; 95% confidence interval [CI] 325–429) vs NORM (352 W; 95% CI 299–404; P < .001) when participants (n = 4) completed the trials in the following order: NORM-DEC, NORM, HYPER-DEC, HYPER. Conclusions: Cycling performance improved with acute exposure to hyperoxia. Mechanisms for the improvement were likely physiological; however, improvement in a deception trial suggests an additional placebo effect. Finally, a particular sequence of oxygen deception trials may have built psychophysiological belief in cyclists such that performance improved in a subsequent normoxic trial.
Keywords
exercise reserve, feedback, placebo, pacing strategy, oxygen content
Date
2019
Type
Journal article
Journal
International Journal of Sports Physiology and Performance
Book
Volume
14
Issue
7
Page Range
949-957
Article Number
ACU Department
Centre for Exercise and Nutrition
Faculty of Health Sciences
Faculty of Health Sciences
Collections
Relation URI
Source URL
Event URL
Open Access Status
Published as green open access
License
File Access
Open
Controlled
Controlled
Notes
Accepted author manuscript version reprinted, by permission, from International Journal of Sports Physiology and Performance, 2019, 14 (7), pp. 949 - 957, https://www.doi.org/10.1123/ijspp.2018-0335 . © Human Kinetics, Inc.