Acute Apnea Does Not Improve 3-km Cycling Time Trial Performance

Area of Science:

• Sports Science
• Exercise Physiology
• Human Performance

Background:

• Intense exercise and acute apnea can cause spleen contraction, releasing red blood cells and increasing hemoglobin concentration ([Hb]).
• This physiological response suggests a potential ergogenic aid for endurance activities.

Purpose of the Study:

• To determine optimal apnea modalities for acutely increasing [Hb].
• To investigate if prerace apnea, using identified optimal modalities, enhances 3-km time trial performance.

Main Methods:

• Part 1: Assessed [Hb] changes in 11 males across 12 apnea protocols varying in mode, frequency, and intensity.
• Part 2: Evaluated 3-km cycling time trial performance in 12 subjects under apnea, control, and placebo conditions post-warm-up.
• Measured V˙O2 kinetics during submaximal cycling under control and apnea conditions.

Main Results:

• A single apnea during warm-up showed a positive trend in [Hb] pattern and potentially improved V˙O2 kinetics.
• No significant differences in 3-km time trial performance were observed between apnea, control, and placebo conditions.
• Key performance indicators like power output, V˙O2, heart rate, and lactate levels remained unaffected by the apnea interventions.

Conclusions:

• The transient increase in [Hb] and potential V˙O2 kinetics improvement from apnea are likely overridden by standard warm-up protocols.
• Prerace apnea, under the tested conditions, does not confer a performance advantage in a 3-km cycling time trial.