The Potential to Change Pacing and Performance During 4000-m Cycling Time Trials Using Hyperoxia and Inspired...

Area of Science:

• Exercise Physiology
• Sports Science
• Human Performance

Background:

• Acute exposure to hyperoxia (inhaled oxygen concentration > 21%) can enhance endurance exercise performance.
• The psychological impact of perceived hyperoxia, independent of physiological effects, is less understood in athletic contexts.

Purpose of the Study:

• To investigate whether deception regarding fraction of inspired oxygen (FiO2) content can improve cycling time-trial (TT) performance.
• To explore the potential placebo effect of perceived hyperoxia on athletic performance.

Main Methods:

• Fifteen trained male cyclists completed six 4000-m cycling TTs under varying FiO2 conditions (normoxia and hyperoxia).
• Trials involved deception, where cyclists were misled about the FiO2 they were inspiring (e.g., receiving hyperoxia but believing it was normoxia).
• A specific trial sequence was tested to assess the impact of accumulated deception on subsequent normoxic performance.

Main Results:

• Cyclists demonstrated greater power output and faster TT performances when inspiring hyperoxic air, regardless of whether they were truthfully informed or deceived.
• Performance significantly improved in a final normoxic trial (NORM-INFORM) following a specific sequence of deception trials.
• A subset of participants (n=4) showed notable performance gains in the NORM-INFORM trial compared to baseline normoxic trials.

Conclusions:

• Acute hyperoxia enhances cycling performance, likely through physiological mechanisms.
• The observed performance improvements during deception trials suggest a significant placebo effect associated with perceived hyperoxia.
• A specific regimen of oxygen deception trials may foster a psycho-physiological belief, leading to enhanced performance even under normoxic conditions.