Could Sodium Bicarbonate—A Common Cooking Ingredient—Be a Hidden Fitness Enhancer?

Ken Yu

June 15, 2023 • 3 min read

An increasing number of athletes are incorporating sodium bicarbonate supplementation into their routines to boost performance, and the scientific rationale behind this practice is compelling. The human body tightly regulates its pH within a slightly alkaline range (7.35–7.45) to optimize vital biological processes, including blood oxygenation and aerobic cellular respiration. pH homeostasis is maintained via two primary mechanisms: the respiratory system regulates carbon dioxide levels, while the urinary system modulates bicarbonate (HCO₃⁻) reabsorption and excretion (1).

During high-intensity exercise, oxygen demand outpaces supply, forcing the body to depend on the anaerobic energy system for adenosine triphosphate (ATP) production (2). This pathway relies primarily on glycogen for rapid energy but generates lactate—a performance-limiting byproduct. The hydrogen ions (H⁺) released from lactate are hypothesized to induce the characteristic muscular burning sensation by exacerbating acidosis once the anaerobic threshold is exceeded. With consistent anaerobic training, the kidneys adapt to produce more bicarbonate to buffer H⁺ accumulation, extending the duration of neutral blood pH (3).

Pretraining sodium bicarbonate supplementation can elevate systemic bicarbonate levels, enabling more rapid and efficient neutralization of muscular acidosis—thereby supporting sustained high-level performance (1).

Sodium bicarbonate (NaHCO₃)—a white, crystalline alkaline powder with a pH of 8.4—possesses inherent acid-neutralizing properties (3). A comprehensive meta-analysis conducted by the International Society of Sports Nutrition found that sodium bicarbonate supplementation enhances performance across a wide range of muscular endurance activities, including cycling, running, swimming, rowing, CrossFit, combat sports (e.g., boxing, judo, karate, taekwondo, wrestling), high-intensity interval training (HIIT), and skill-based sports (4). The ergogenic effects of sodium bicarbonate are well-documented, safe, and effective, with minimal adverse effects when used appropriately (5).

A separate meta-analysis demonstrated that sodium bicarbonate supplementation improves mean power output by 1.7% in high-intensity, short-duration races (6). Its benefits are most pronounced for vigorous activities lasting 30 seconds to 12 minutes—durations where the lactic acid system dominates energy production. Research also confirms that supplementation enhances muscular endurance during repeated high-intensity intervals (6). For example, one study found that baking soda supplementation likely improves performance in 2000-meter rowing events, particularly during the latter half (7). Conversely, as exercise duration extends beyond 12 minutes, the body shifts to the aerobic energy system, reducing the need for acid-buffering supplementation (6).

Beyond its physiological effects, sodium bicarbonate may also exert a psychological placebo effect: by dampening the perception of muscle fatigue, it can indirectly enhance overall performance (8).

Dosage and Timing Guidelines

Recommended dosages range from 0.2 to 0.5 grams per kilogram of body weight (g/kg BW), with an optimal dose of approximately 300 milligrams per kilogram of body weight (mg/kg BW)—a level that maximizes benefits while minimizing adverse effects (5).

Supplementation timing exhibits significant interindividual variability, but athletes can optimize peak performance through personalized adjustment (5). A typical single-day protocol involves consuming the dose 60–180 minutes prior to exercise, either as a single bolus or divided into smaller doses (5). Multiday protocols—where 100–200 mg/kg BW doses are administered 3–7 days before an event—are also effective and reduce the risk of acute side effects on competition day.

Synergistic Combinations

To augment the performance-enhancing effects of sodium bicarbonate, co-supplementation with caffeine, beta-alanine, and/or creatine is often employed:

• Caffeine: A study of 6 elite 200-meter swimmers found that combined sodium bicarbonate and caffeine supplementation improved performance (9).

• Creatine: A double-blind, placebo-controlled trial involving trained men performing 6 × 10-second maximal sprints (60-second rest) on a cycle ergometer showed that sodium bicarbonate (SB) + creatine (CR) increased peak power by 7%—compared to 4% with CR alone. Additionally, SB+CR maintained relative peak power longer than other groups (10).

• Beta-Alanine: A crossover study of 16 swimmers found a high probability that co-ingestion of beta-alanine and sodium bicarbonate enhanced performance, with 6 of 7 athletes swimming faster post-supplementation (11). However, further research is needed to confirm these findings.

Adverse Effects

The primary adverse effect associated with sodium bicarbonate ingestion is gastrointestinal (GI) distress. Upon reacting with gastric acid, sodium bicarbonate produces sodium chloride, water, and carbon dioxide (CO₂). Excess CO₂ can elicit GI symptoms including nausea, bloating, flatulence, and abdominal pain. In cases of excessive intake, more severe symptoms such as diarrhea or vomiting may occur (12).

Practical Recommendations

For athletes considering sodium bicarbonate supplementation, a prudent approach involves:

1. Initiating with a low dose (administered at least 2 hours pre-exercise) to assess individual tolerance.

2. Gradually increasing dosage and adjusting timing to optimize outcomes (13).

Works Cited