Acetazolamide does not alter endurance exercise performance at 3,500-m altitude

Area of Science:

• Sports Medicine
• Altitude Physiology
• Pharmacology

Background:

• Acetazolamide (AZ) is widely used for acute mountain sickness (AMS) prevention.
• Previous research on AZ's effect on exercise performance at altitude is inconclusive.
• Understanding AZ's impact on exercise capacity is crucial for athletes and high-altitude travelers.

Purpose of the Study:

• To investigate the effect of acetazolamide (AZ) on endurance exercise performance during simulated high-altitude exposure.
• To evaluate if 500 mg/day of AZ impairs time-trial performance at 3,500m.
• To assess AMS incidence and physiological responses alongside exercise performance.

Main Methods:

• A crossover study design involving 10 men exposed to 3,500m hypobaric hypoxia for 30 hours.
• Participants received either 500 mg/day acetazolamide (AZ) or a placebo.
• Exercise testing included a 2-mile self-paced treadmill time-trial conducted 2 and 24 hours after ascent.

Main Results:

• Acetazolamide (AZ) significantly reduced AMS incidence from 40% (placebo) to 0%.
• Oxygen saturation was higher with AZ compared to placebo at both 2 and 24 hours.
• No significant difference in 2-mile time-trial performance was observed between AZ and placebo groups at either time point.

Conclusions:

• Acetazolamide (500 mg/day) does not impair endurance exercise performance at 3,500m simulated altitude.
• AZ effectively mitigates AMS symptoms while maintaining exercise capacity.
• This study provides evidence supporting AZ use for high-altitude expeditions without compromising physical performance.