Effect of sodium bicarbonate on prolonged running performance: A randomized, double-blind, cross-over study

Area of Science:

• Exercise Physiology
• Sports Science
• Nutritional Supplementation

Background:

• Exercise performance is limited by the body's capacity to buffer pH decreases.
• Sodium bicarbonate (BICA) is studied for its ergogenic potential in high-intensity exercise.
• Research on BICA's effects on prolonged endurance running performance is limited.

Purpose of the Study:

• To evaluate the ergogenic effects of oral sodium bicarbonate (BICA) supplementation on exhaustive endurance running performance.
• To assess BICA's impact on time to exhaustion and physiological markers during high-intensity running.

Main Methods:

• Double-blind, randomized cross-over study with 18 trained runners.
• Participants ingested either BICA (0.3 g/kg) or placebo before exhaustive graded exercise tests and constant load tests.
• Measurements included time to exhaustion, respiratory gas exchange, heart rate, blood gases, and lactate concentration.

Main Results:

• Maximal running speed was significantly higher with BICA compared to placebo.
• Time to exhaustion in prolonged high-intensity running did not differ significantly between conditions.
• BICA supplementation led to higher blood lactate levels and maintained blood pH, but caused gastrointestinal side effects in most participants.

Conclusions:

• BICA enhances maximal performance, likely due to increased anaerobic glycolysis, but does not improve prolonged high-intensity running endurance.
• Metabolic acidosis may not be the sole dominant factor limiting endurance performance.
• Further research is needed to reconsider the role of metabolic acidification in muscular fatigue.