Beta-alanine andsodium bicarbonate are some of the most popular ergogenic supplements (supplementsintended to enhance physical performance, stamina, or recovery)on the market. Why? Most athletes assume that they actually work.
And it didn’t take long before supplement manufacturers started mixing the two. They weren’t just jocks in lab coats mixing random viles, either—many scientists actually predicted a synergistic effect from mixing the two.
But recent research suggests that not only does combining the two show no meaningful gain in athletic performance, but that both supplements on their own are ineffective.
However, because of limitations in the study, I disagree.
Danaher, et al. (2014) found no effect of combining both during performance test with fixed intensity and volume. And if you look at the study design of the latest bicarbonate + beta-alanine cocktail (or BB, for short) study by scientists from theUniversity of Sao Paulo (da Silva 2018), you again find thatno meaningful performance gains occurred.
Yet, Tobias et al. (2013) tested upper body performance and didn't limit either intensity or volume anddidseeincreased performance. Actually, the BB almost doubled the total work the subjects performed.
So what gives? Is the BB cocktail a flop, or a win?
Interestingly, it appears that da Silva’s study (which didnotshow any meaningful increase in performance) capped training intensity and total volume.
Let’s take a closer look at the most recent study byda Silva 2018.
The scientists had their reasons to standardize the workload. Without this standardization, the team wouldn't have been able to create an objective study. For example, scientists needed a guarantee that one group won't exercise 10 minutes longer or at 10% higher work rates than the other.
But let's (re-)address that later. For now, let’s take a closer look at the other key parameters of what I feel is a well-designed, interesting, and eventually highly educative study, despite (or because of) the lack of significant performance differences:
Figure 1: Experimental design (upper panel) and overview of the main trials (lower panel). BA β-alanine, SB sodium bicarbonate, PL placebo, CaCO3 placebo for sodium bicarbonate, lac plasma lactate analysis, gas blood gas analysis, HICT-110% high-intensity cycling test performed at 110% of Wmax (da Silva 2018)
As it is necessary for any double-blind, parallel-group, placebo-controlled trial, the participants were randomly allocated to the BA (β-alanine + placebo; n = 20, 3 drop-outs), SB (placebo + sodium bicarbonate; n = 20, 3 drop-outs), BASB (β-alanine + sodium bicarbonate; n = 20, 1 drop-out), or PLA (placebo + placebo; n = 20, 2 drop-outs) groups and asked to identify their group allocation (i.e., BA or maltodextrin and SB or calcium carbonate) to verify the blinding process.
Maltodextrin (the abstract falsely claims it was dextrose, which would be a very bad placebo due to its characteristic taste) and calcium carbonate were the placebos for BA and SB. Moreover, the randomisation was performed in blocks of 4 with groups being matched for time to complete a 30-kJ test to avoid significant baseline performance differences between the groups.
And finally, blood was sampled before and in-between exercise bouts and the time trial, respectively, and the VO2 consumption measured continuously before and during the HICT110% test.
That brings me to the first issue with the the study.
Not really, because one gives you the tingles and the other...the runs. And trained athletes would certainly recognize these effects.
The fact that three volunteers reported paresthesia (the tingles) with BA (BASB group) and nine participants (SB: 5; BASB: 4) reported gastrointestinal discomfort after ingesting sodium bicarbonate, confirms that blinding is not possible for the two agents.
Even though seven volunteers in the BA, five individuals in SB, six in BASB, and five in the PLA group rightly identified the arm (BA/PLA) they had been randomized to, the Fischer’s exact test showed a p-value of p = 0.85 for BA and p = 0.82 for SB, respectively. Apparently, it was a double-blind study in spite of tingling and tummy aches.
Figure 2: Effects of β-alanine (BA) and sodium bicarbonate (SB) on the time to complete 30-kJ time-trial performance. The grey bar on crepresents the 95% confidence interval of the coefficient of variation of the test. Positive and negative confidence intervals crossing zero on dwere deemed nonsignificant (da Silva 2018).
Now, as previously announced, da Silva et al. did not find a significant effect of any of the three supplementation protocols on the subjects exercise performance.
However, results did suggest non-significant performance improvements, with the largest effectsize being and a borderline significant effect being observed in the BA + SB group.
What does all this mean?
There was a measurable effect, with the most meaningful in the sodium bicarbonate and beta-alanine group, but no significant performance increases.
If the increase in performance wasn’t significant, why would you care?
I’m glad you asked.
These results are not actually surprising when you consider the structure of the study.
You see, the benefits of the supplements depends on the build-up of sufficient amounts of H+ (good ol’ hydrogen) in a process called buffering. You can think of this chemical reaction like a sponge soaking up water—at a certain point, it is so saturated it can’t absorb any more liquid.
Within the very short (~60s) bouts of exercise that was aborted when the subjects hit the 30-kJ of exercise mark, the H+ requirement probably wasn't met. Or with consideration of the non-significant benefits, it was at least not met to a sufficient degree.
Figure 3: The amelioration of the decline in blood pH and bicarbonate shows that the SB treatment did what it was supposed to do - work as a buffer. However, asFigure 2 shows, the differences in pH and blood HCO3 were obviously too small to make a significant difference during the very short 30kJ performance test (da Silva 2018).
As Figure 3 shows, this doesn't mean that the buffers didn't work.
As you can see, sodium bicarbonate successfully buffered the decrease in blood pH and we can assume that a muscle biopsy would have shown slightly reduced intra-cellular H+ levels due to beta-alanine.
What this study really shows is that the biochemical differences to the control trials were too small and the inter-group variance too large to detect significant performance benefits.
My plot of the effect sizes for the impact of beta-alanine (BA), sodium bicarbonate (SB), the combination of both (BASB), and placebo on the glycolytic energy contribution illustrates quite nicely that it's bicarbonate, not beta-alanine that will keep you going towards the end of a team sport event or in the sprint before the finish line.
It appears that sodium bicarbonate—not beta-alanine—increases the important glycolytic energy contribution during short bursts of high-intensity exercise.
This is significant because it's often said that beta-alanine gives you an increased ability to tap into your glycogen stores that will provide the coveted “second wind.”
Now, if we assume that the sodium bicarbonate advantage is not a result of bicarbonate messing with the indirect measurement of the glycolytic energy contribution (remember, no biopsies were performed), da Silva et al. suggest that absence of this benefit in beta-alanine may be due "to the total amount of H+ that can be neutralised by the working muscles" by sodium bicarbonate v. beta-alanine, respectively.
There were two important limitations of the study the scientists willingly admit in the discussion of the results:
The same must be assumed of the lactate buffering effects of sodium bicarbonate. In the scientists' multiple comparison analysis of the post-HICT-110% plasma lactate levels in the SB group, the latter approached significance (t = − 1.82, p = 0.074), and were significantly higher after the 30-kJ TT in both, the SB only (t = − 2.67, p = 0.01) and the BASB group (t = − 2.61, p = 0.011).
Figure 4: Effects of β-alanine (BA) and sodium bicarbonate (SB) supplementation on the absolute contribution of the energy systems during the HCT-110% test (da Silva 2018). The increase glycolytic flux and improved ability to tap into the readily available glucose sources can be ascribed to the pH buffering effect of SB (Sutton 1981).
Unfortunately, lactate still has an unwarrantedly bad rep (Cairns 2006). It is thus important to note that increased lactate levels are a necessary consequence of an increased use of glucose and by no means a reason to expect performance decrements.
In fact, almost all sodium bicarbonate studies which tested the level of lactate in the subjects' blood found it to be significantly increased in the presence of significant performance benefits!
That's something people tend to forget in a day and age where even the superiority of glucose as the #1 substrate for high-intensity exercise is questioned (sorry keto fans, but that's simply what the contemporary evidence says).
While significant effects on the performance markers measured in the study at hand were not observed, da Silva et al. found non-significant increases in exercise performance in both tests, especially, when the two H+ buffers were combined, and a potentially highly relevant 20% increase in the subjects ability to tap into their glycogen stores in the SB and BASB groups.
In competitive sport, this difference may well make the difference between winning an Olympic medal and ending up with a disappointing fourth rank.
Bodybuilders have a sign. elevated muscle carnosine levels, it is yet not clear if that's an adaptational response to prolonged repetitive exposure to low muscle pH, the consumption of high carnosine foods like chicken, supplement use, or the use of anabolic steroids (Tallon 2005). Other studies show that men store more carnosine than women (Mannion 1992), omnivores more than vegetarians (Harris 2007), and that genetic factors which have hitherto only been confirmed in our omnivore 'cousins', the pigs (D'Astous-Pagé 2017), may figure as well. It is thus hardly surprising that the BA research as such yielded highly variable results which are, just as it's the case for the study at hand, difficult to interpret if the changes in muscle carnosine aren't measured.
The statement that sodium bicarbonate and beta-alanine "don't work" should rather read “sodium bicarbonate and beta-alanine exert mea-surable, yet highly variable performance benefits.”
The effects may not have reached statistical significance because
(1) the efficacy of both agents has a high inter-individual variability, with beta-alanine potentially failing in subjects with diet or training related naturally high carnosine levels (cf. Figure 5) and sodium bicarbonate countering its own ergogenic effects via gastrointestinal distress (which was reported by nine participants in the study at hand), or because
(2) H+ buffers excel in exercise capacity tests, i.e. tests in which you exert yourselves to the point of volitional exhaustion, as opposed to performance tests with a fixed point like the 30 kJ test in the study at hand, or because
(3) the results of the study (despite being one of the better-powered investigations), may still "lack of statistical significance [...] due to insufficient statistical power to detect small effects" (my emphasis inda Silva 2018).
It's also possible that all three contributed synergistically to the lack of statistical significance of the results.
Instead of trying to make a general statement about the two ergogenics, which have also made the ISSN's TOP5 list of OTC ergogenic supplements, only recently (Kerksick 2018), we should use the publication of the study at hand to remind ourselves that the benefits of any supplement are specific to the sport, exercise, and even muscle group engaged.
Figure 6: With an upper-body Wingate test, the study byTobias et al. (2013) I covered5 years ago used didn't just use an exercise capacity test that didn't limit the total work done, but also tested the effects on a different muscle group - et voila: Tobias et al. found significant increases in total work and mean power with the combination of BA +SB.
So, what should you do? Well, one thing should be obvious:
Don’t throw away your 5kg bag of sodium bicarbonate and your 1kg tub of beta-alanine. Even though the performance benefits in the study at hand were at best borderline significant, there's a reason that both agents have been around for years (beta-alanine) and decades (bicarbonate).
In the absence of sufficient research to tell for sure who will and who won't benefit from using them, it’s best to make up your own mind on their effectiveness for you.
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