Sodium Bicarbonate Ingestion in a Fasted State Improves 16.1-km Cycling Time-Trial Performance

Area of Science:

• Exercise Physiology
• Nutritional Supplementation

Background:

• Sodium bicarbonate (SB) is a known ergogenic aid for high-intensity, short-duration exercise.
• Its effects on prolonged high-intensity exercise, like a 16.1-km cycling time trial, are less understood.

Purpose of the Study:

• To investigate the impact of pre-exercise sodium bicarbonate (SB) ingestion on 16.1-km cycling time trial performance.
• To compare the efficacy and gastrointestinal tolerance of SB in gelatine capsules (SB-G) versus enteric capsules (SB-E).

Main Methods:

• Ten trained male cyclists participated in a randomized crossover study.
• Participants ingested 0.3 g·kg⁻¹ body mass of SB in either gelatine or enteric capsules, or a placebo, before simulated 16.1-km cycling time trials.

Main Results:

• Sodium bicarbonate ingestion significantly improved cycling time trial performance compared to placebo (P=0.014).
• Performance time was reduced by 34.4s (SB-G) and 40.4s (SB-E) (P<0.05).
• Gastrointestinal symptoms were significantly lower with enteric-coated capsules (P<0.001).

Conclusions:

• Acute pre-exercise sodium bicarbonate ingestion enhances buffering capacity, improving endurance cycling performance.
• SB supplementation is a viable ergogenic strategy for 16.1-km cycling time trials.
• Enteric-coated SB offers improved gastrointestinal tolerance, potentially maximizing ergogenic effects.