Baking soda? Check out this kitchen cupboard staple’s role in exercise performance.
Interestingly, December 30th is Bicarbonate of Soda Day – odd to think that we dedicate a day to commemorate a compound when so many exist. Historically, sodium bicarbonate (baking soda) and sodium carbonate (soda ash) were both discovered on this day in 1791 by a French chemist, Nicolas Leblanc, and both compounds have since been used in a variety of industrial applications (e.g., cooking, paint, pest control, disinfectants). Subsequently, they hold great importance to mankind, but why discuss them in the context of fitness?
One compound, sodium bicarbonate, also serves an important role within our body – functioning as our lactate (and hydrogen) buffer to preserve blood pH and enable us to keep exercising during intense bouts of activity. When we exercise, hydrogen ions (H+) are produced during the breakdown of carbohydrates (glycolysis) and through the utilization of our energy molecules – ATP. Under steady-state (aerobic) exercise conditions, these H+ ions normally pass to the mitochondria for energy production with oxygen, but under non-steady-state (anaerobic) exercise, these ions begin to accumulate as they cannot all be cleared given limitations in oxygen availability. This results in acidosis (lowered tissue pH) due to accumulated H+ which will slow and ultimately stop glycolysis.
Because H+ cannot be directly removed from the cell, it is combined with excess pyruvate (also produced during glycolysis) to form lactic acid, which can then be removed and placed into the blood (i.e., this enables the muscle to continue working). While the muscle has been temporarily alleviated of this problem, it is the blood who has inherited the problem. It is important to recognize that the human body constantly produces lactate, and in small dosages, it is well-tolerated, but any accumulation can become disastrous because blood acidosis (lowering blood pH) can potentially impair or damage protein structures like red and white blood cells, enzymes and hormones. Fortunately, our blood has the capacity to tolerate some accumulation due to the presence of sodium bicarbonate (NaHCO3), a base and our principal hydrogen buffer. Technically, the more of this buffer you contain in the blood, the greater your capacity for tolerating intense exercise. Does this imply ingesting large quantities of sodium bicarbonate in our diets to increase this buffer? Yes and no – the ingestion of “some” quantities does help, but too much is potentially harmful – causing a variety of side-effects ranging from nausea, diarrhea and stomach ulcers to blood alkalosis where the blood pH rises too high.
Expanding blood volume, achieved primarily through aerobic training, is one effective method to enhance the blood’s ability to hold more sodium bicarbonate without altering the blood pH. Aerobic training can expand blood volume by 12-to-20% to accommodate more red blood cells, but this same expansion also allows for a greater and sustained quantity of sodium bicarbonate to be stored which in turn will improve anaerobic capacity.
Another commonly used strategy to temporarily (a few hours) increase sodium bicarbonate levels in the blood, with minimal side-effects, is via a specific nutritional intervention. This is done by ingesting sodium bicarbonate (baking soda) at a recommended dose of 0.2 – 0.4 g per Kg of body weight (0.1 – 0.18 g per pound lb.) mixed with one liter (33.8 oz.) of fluid 60-120 minutes before exercise. For example, a 160-pound individual would ingest between 16 and 29 grams in one liter of fluid. Keep in mind, however, that is might require flavoring because of the poor taste of sodium bicarbonate. This strategy is supported by various studies that demonstrate improved anaerobic capacity and performance associated with this intervention.
Hence, while we recognize the many benefits to mankind from Leblanc’s discoveries on December 30th, let’s not forget that this compound, which exists naturally in our blood can have implications on our own performance and ability to attain many of our goals.