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Image 1: Pure baking soda is not (yet?) a staple of the supplemental arsenal of many athletes. The scientific evidence with regard to its immediate ergogenic effects is ambigious and the mere presence of the word "sodium" in "sodium bicarbonate" scares the hack out of those athletes (bodybuilders and figure competitors) who may benefit most from a few grams of this potent alkalizer. |
"Sodium"! This word alone is usually enough to scare bodybuilders and fitness athletes to death. "Sodium!? Isn't that the stuff that makes me look bloated?" The answer is easy: No! While
sodium will help you retain enough water in your body to perform in the gym, the amount of sodium you ingest usually has little impact on the amount of water you will be holding, only when you start modulating your sodium intake, your body will react with changes in the renin-andiotensin-aldosterone system and you will be fluctuating "nicely" back and forth from super-bloated to weak and dehydrated... this is yet commonly ignored within the fitness community and thus it is no wonder that most
supplement producers are anxious not to include any ingredients in their products that would show up on the label as "sodium" - after all, there are still costumers out there who have not enrolled at the SuppVersity and will thusly run away screaming as soon as they take a closer look on the label of a product they were just about to buy.
It is thusly no wonder that (at least to my knowledge) KreAlkalyn, where NACO3 is the working ingredient of the highly advertised buffering system, is the only product using sodium bicarbonate, or soda ash, as it is also called, as one of its main constituents (more on this topic in the
SuppVersity Creatine Special).
In medical settings NACO3 was and, in parts, still is still the "drug" of choice to combat acute acidosis. It is thus no wonder that Daniel J. Peart and his colleagues from the
University of Hull in the United Kingdom, as well as the
Bond University in Queensland, Australia are not the first scientists who speculated that athletes, especially those competing in (primarily) anaerobic sports, could benefit from the alkalizing effects of their grandmothers' secret weapon in the war against fungi and bacteria on her kitchen furnishings (
Peart. 2011).
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Image 2: "Cholesterol is the devil and sodium is his little brother!" Everyone who still believes everything the medical orthodoxy says, please raise your hands! |
A note on the dangers of "salt": Firstly,
baking soda is "only" ~28% sodium, which means that for every 4 grams you ingest you get roughly 1 g of sodium. Secondly, it is arguable how much of the sodium is effectively taken up and will be floating around in your blood. As T. Lakhanisky points out in his dossier for the Belgian government: "The
uptake of sodium, via exposure to sodium carbonate, is much less than the uptake of sodium via food. Therefore, sodium carbonate is not expected to be systemically available in the body." (
Lakhanisky. 2002) And thirdly, there is more and more evidence that suggests that
the chloride rather than the sodium content of common table salt (NaCl = NatriumChloride) is the root cause of "sodium induced hypertension" in "sodium sensitive" individuals / animal models. Only recently, a study by Schmidlin et al. showed that chloride loading induced hypertension in the stroke-prone spontaneously hypertensive rat
despite profound sodium depletion (
Schmidlin. 2010). So, if you asked me, rather than pointing at salt as the #2 on the list of greatest evils (obviously cholesterol is still #1, here)
the medical orthodoxy would be better advised to address the imbalances between sodium and potassium, which are so characteristic of the western diet, instead of painting
yet another black and white picture where sodium is the bad guy and potassium the dangerous mineral that cannot be sold OTC in dosages >80mg.... but hey, this would be the topic for a whole new blogpost and as gross as it may sound, the chance that you get diarrhea from the baking soda is probably 1000x higher than the remote possibility of increases in blood pressure. A 1990 study by Luft et al. even found that the blood pressure of 10 mildly hypertensive and normal subjects
decreased by 5mmHg after 7 days in the course of which they drank 3 liters of sodium bicarbonate containing water per day (
Luft. 1990)
In their study, Peart et al. had a group of seven recreationally active men (age 22.3 ± 2.9 years,
height 181.6 ± 4.5 cm, body mass 78.1 ± 8.1 kg, and physical activity 4.2 ± 0.6 h/week) "with no history of supplementing their diet with ergogenic agents" perform a
4-min bout of all-out exercise on an air-brake cycle ergometer on three different occasions (spaced exactly 1 week apart). While the first was an acclimatization session the second and third bout were performed after the ingestion of either 0.3g/kg sodium bicarbonate (trial 2) or plain table salt (trial 3) in "low-energy flavored water" 90 minutes prior to exercise.
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Figure 1: Blood ph levels after ingestion of placebo or 0.3g/kg sodium bicarbonate (data adapted from Peart. 2011) |
As you can see in figure 1, the ingestion of ~23.4g of baking soda produced a rather slight but significant shift towards a more alkaline blood ph level (compared to placebo), which became much more pronounced after the exercise bout (p<0.003). Interestingly,
there was yet no significant difference (p>0.26) in exercise performance as measured by average and peak power (means ± SD; average power 292 ± 43 W vs. 291 ± 50 W; peak power 770 ± 218 W vs. 775 ± 211 W; work completed 71 ± 10 kJ vs. 68 ± 10 kJ) between the groups.
Baking soda: A non-ergogenic ergogenic?
The latter observation, i.e. no or statistically non-significant increases in acute exercise performance upon sodium bicarbonate ingestion, stands in line with ~75% of the previous findings, a recent meta-analysis by Carr et al. summarizes as follows:
The remaining 38 studies and 137 estimates for sodium bicarbonate
produced a possibly moderate performance enhancement of 1.7% (90%
CL ± 2.0%) with a typical dose of 3.5 mmoL/kg/BM (∼0.3 g/kg/BM) in a
single 1-minute sprint, following blinded consumption by male athletes.
In the 16 studies and 45 estimates for sodium
citrate, a typical dose of 1.5 mmoL/kg/BM (∼0.5 g/kg/BM) had an unclear
effect on performance of 0.0% (±1.3%), [...]
Study and subject characteristics had the following modifying small
effects on the enhancement of performance with sodium bicarbonate:
an increase of 0.5% (±0.6%) with a 1 mmoL/kg/BM increase in dose; an
increase of 0.6% (±0.4%) with five extra sprint bouts; a reduction of
0.6% (±0.9%) for each 10-fold increase in test duration (e.g. 1-10
minutes); reductions of 1.1% (±1.1%) with nonathletes and 0.7% (±1.4%)
with females. Unexplained variation in effects between research settings
was typically ±1.2%.
Despite these rather mediocre immediate effects of bicarbonate pre-loading, the main finding of the study at hand hints at hitherto overlooked long(er)-term immune benefits the consumption of sodium bicarbonate might have.
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Figure 2: HSP-72 expression in mono- and lymphocytes in response to anaerobic exercise after ingestion of placebo or 0.3g/kg sodium bicarbonate (data adapted from Peart. 2011) |
As you can see in figure 2 the stress-induced HSP-72 expression in white blood cells (lymphocytes and monocytes) in response to the HIT exercise was almost completely abolished. Along with the nullification of the already low amount of oxidative stress (cf. T-BARs in figure 3), these results suggest
that bicarbonate supplementation has a stress-protective effect on immune cells during anaerobic exercise.
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Figure 3: Oxidative stress due to anaerobic exercise as measured by TBAR expression after ingestion of placebo or 0.3g/kg sodium bicarbonate (data adapted from Peart. 2011) |
It is yet important to note that the scientists point out that
it "is unclear at this stage whether the attenuation was due to a reduced state of acidosis, reduced oxidative stress or a combination of both." Moreover, it is difficult to say which consequences this would have on future bouts of exercise and whether and to which degree athletes would actually benefit - or, if we think of the
hormesis hypothesis and the ongoing debate concerning the effects of antioxidants on exercise induced adaptations - maybe even compromise their performance, would yet need further investigations.
We may yet assume that, just as it is the case with antioxidants, the
dosage will have to be matched to the individual workload to see optimal results. With people exercising just enough to see any adaptations seeing no and people who do crossfit 2x a day seeing the most beneficial results from (partially) blocking the exercise induced oxidative stress.