Monday, October 15, 2012

Beta-Alanine Does not Make it From Bench to Pool Side: Are the Effects Too Short-Lived? Is Swimming the Wrong Sport? Or Was the Dosage of 3.2g/day Simply Too Low?

Michael Phelbs holding his record-setting 19th Olympic medal. According to the results of the latest Australian study on the real-world effects of beta alanine supplementation during the training and competitive season in elite national level swimmers the touted ergogenic is unlikely to have helped him win only one of those.
As the headline of today's SuppVersity post already suggests, a recently published paper by scienstists from the Australian Institute of Sport, the Institute of Sport, Exercise and Active Living (ISEAL), and the Queensland Sport and Athletics Centre (QSAC) does unfortunately raise about as many new questions about the real-world value of beta-alanine supplementation as it answers. And that despite the fact that the researchers originally set out to bridge the existing gap between the existing research on beta-alanine supplementation, which involves mainly non-elite participants and laboratory-based performance tests, which do not necessarily relate to elite level sport, on the one hand, and the real world effects of beta-alanine "supplementation in elite athletes on training and competition in a real-world setting" (Chung. 2012), on the other hand.

Beta alanine doesn't make it from bench to pool edge...

In the course of the 10-week study the researchers measured the exercise performance, as well as lactate levels, blood pH and bicarbonate levels of the 60 (34 male and 26 female)elite/sub-elite swimmers they had convinced to take part in the study after they had taken part in standardized tests, which were designed to to tailor to the athletes' individual race distances...
Figure 1: Schematic timeline of study design (Chung. 2012)
  • Sprint: 4 × 50-m on a 3 min cycle (maximal) + 100-m maximal effort 
  • Middle distance: 6 × 50-m on a 2 min cycle (maximal) + 200-m maximal effort 
  • Distance: 8 × 50-m on a 1.5 min cycle (maximal) + 200-m maximal effort 
...at the beginning, after 4 weeks and at the end of the study (week 10). With the exception of the testing days, the athletes followed their own training and competition schedule while supplemented with
  • 4.8 g per day (two 800 mg tablets, three times daily) of beta-alanine or placebo with meals in the initial 4-week loading phase and
  • 3.2 g/day (two tablets, twice daily) of beta-alanine or placebo for the remainder of the study period (6-week maintenance phase). 
Needless to say that all supplements, regardless of whether they contained the active sustained release beta-alanine from Musashi (Australia) or the maltodextrin placebo from GMP Pharmaceuticals, looked absolutely identical.

Were the results skewed due to the insufficient blinding of the study? No, "the beta-alanine supplemented swimmers who correctly guessed their treatment did not perform better that those who believed they were on placebo." (Chung. 2012)
Yet despite these precautions and the use of porportedly tingling free sustained preparations 10 out of 12 respondents in the BA group (total participant in this group n=22) who correctly guessed the identity of the supplement they received reported mild paraesthesia. In the placebo group on the other hand, "12 out of 19 respondents guessed correctly, attributing it to the absence of side effects (5 respondents) and taste (3 respondents)." (Chung. 2012)

And that did not work at all?

When the title of this post says that "beta-alanine does not make it from bench to pool side", this is actually not quite correct. With a reference value of 0.3% for the smallest worthwhile change used to compare the competition performance and an outcome measure being deemed unclear when the confidence interval crossed limits for both a substantially positive and negative effect, the statistical analysis of the data of the 43 swimmers that did not drop out due to injuries or simply lost interest in the study at one point or another, showed that
"[t]here was an unclear effect (0.4%; ±0.8%, mean, ±90% confidence limits) of beta-alanine on competition performance compared to placebo with no meaningful changes in blood chemistry, as well as an unclear effect at ten weeks (−0.2%; ±1.5%) and no meaningful changes in blood chemistry." (Chung. 2012)
It is therefore hard to debate the researcher's conclusion that contrary to the results observed in artificial laboratory settings, "[b]eta-alanine supplementation appears to have minimal effect on swimming performance in non-laboratory controlled real-world training and competition settings." (my emphasis; Chung. 2012)

Couldn't it be that 4 weeks and/or 4.8g instead of 3.2g the magic numbers?

Whether this "failure" is only a result of the "non.laboratory controlled real.world training and competition setting", appears yet questionable. After all, the data in figure 2 goes to show you that there are "small difference" in lactate concentrations, specifically in week 4:
Figure 2: Blood ph and bicarbonate concentrations after the standardized exercise tests in week 0, week 4 and week 10 expressed relative pre-test values (left) and corresponding lactate concentration (right) expressed relative to average in all trial (11.6 mmol/l; data adapted from Chung. 2012)
And while lower lactate levels are usually indicative of lower exercise performance due to lower buffering (and thus higher lactic acid production), the higher intra-cellular buffer capacity due to  the beta-alanine induced increases in carnosine stores, did yield even smaller, but measurable perfomance increases in the corresponding tests in week 4, when the race perfomance times transiently improved by −1.3% in the beta alanine group.

Based on the latter observation, we can negate the second of the three questions in the headline, because if we assume that these performance increases, as transient as they may have been were real, this means that swimmers can benefit from beta-alanine supplementation - even if the benefit is marginal. We are now however still left with the first and second question from the headline, I want to briefly address before we go on to the implications and conclusion of today's blogpost.
Figure 3: Muscle carnosine levels in bodybuilders and untrained controls (data based on Tallon. 2005)
  1. Are the effects of beta alanine only short lived and chronic supplementation useless? This hypothesis would actually be somewhat supported by the results of Hill et al. who found that the total work done during a cycling capacity test increased by 13% over placebo after 4 weeks but kept increasing only 3.2% in the remaining 6 weeks, before the study ended (Hill. 2007). This is clear cut evidence for the non-linear and certainly not accumulative nature of the ergogenic effects of beta-alanine (and a vast amount of other processes in nature, by the way, linearity is more or less the exception from the rule, so to say ;-)

    Moreover these effect were observed in recreationally active men, in whom the effects of beta-alanine supplemetation are probably lower to begin with, we could speculate that this "diminishing returns effect", as you may call it, would be even more pronounced in trained athletes. After all, especially those, in whom muscle carnosine levels actually matter, i.e. sprinters, weight lifters and, as the data in figure 3 goes to show,  bodydbuilders do already have much higher muscle carnosine concentrations than age-matched untrained subjects (in the absence of supplementation, of course!).
     
  2. Do you need a higher dosage than just 3.2g/day if you are an athlete athlete? 15 out of 18 studies in Hobson et al. 2012 meta-review used doses between 4.0 - 6.0g/day (Hobson. 2012). In only four of those studies the subjects were anywhere near "professional" athletes. As mentioned before strength athletes, sprinters and everyone else who would be particularly prone to benefit from beta alanine tends to have already higher intramuscular carnosine levels (cf. figure 3). Against that background, it appears only reasonable to assume that elite athletes would require higher doses of beta-alanine than rookies or non-trained individuals to increase their intramuscular carnosine stores (which is the whole point in supplementing with beta-alanine) even further. On the other hand, it is likewise possible that a further increase simply won't take place or is too small, irrespective of the dose to result in real world performance increases.
And if neither of those two hypothesis holds, it may still all come down to the outcome measures researcher use to gauge the effects. In this regards, Chung et al. rightfully state that their results are actually in accordance with the most recent meta-analysis by Hobson and colleagues (Hobson. 2012), who discussed divergent research findings from studies utilizing “capacity” and “performance” type protocols.
"Hobson and colleagues found that beta-alanine supplementation had a moderate effect on exercise capacity while having no benefit on measures of exercise performance due to the employment of pacing strategies." (Chung. 2012).
Conversely, Chung et al. saw minimal improvements in the high-intensity training “capacity” sets of their standardized testing protocol (the 4-8x 50m sprints), yet not in the far more imporant “performance” measure, i.e. competition component of their investigation.

Figure 4: With a carnosine washout time of at least 9 weeks (in "low responders") there is no reason to take BA chronically (data shows skeletal muscle carnosine in healthy untrained men relative to baseline at week T=-5/-6 after 5-6 weeks of 4.8 g/day β-alanine supplementation; based on Baguet. 2009)
Bottom line: Overall the results of the study at hand do therefore not confute the use of beta alanine as an ergogenic aid, per se. They should however make you reconsider, whether the simple addition of the suggested 3.2g/day of beta-alanine to an at least for some of you already borderline excessive supplement regimen is really necessary and whether shorter, yet maybe higher dose cyclic supplementation at time points, where you are most likely to benefit from the 1-2% performance gain in training capacity (e.g. phases of planned over-reaching, the high volume phase of a macrocycle, etc.) would not be a more prudent way to use beta-alanine. After all, the data in figure 4, though once again from untrained individuals, shows that it takes roughly 9 weeks even in the "low responders" for the increase in skeletal muscle carnosine to be reversed again.

There is no need to take it religiously day in day out, then, because there is as of yet no evidence that a couple of workouts would decrease the tissue level of carnosine, again.In fact, the naturally increased carnosine levels in athletes (see figure 3) would rather suggest that the exact opposite is the case, i.e. that exercise in the presence of an adequate nutrient supply would increase the carnosine buffer of your muscles, anyway.


References:
  • Baguet A, Reyngoudt H, Pottier A, Everaert I, Callens S, Achten E, Derave W. Carnosine loading and washout in human skeletal muscles. J Appl Physiol. 2009 Mar;106(3):837-42. 
  • Chung W, Shaw G, Anderson ME, Pyne DB, Saunders PU, Bishop DJ, Burke LM. Effect of 10 Week Beta-Alanine Supplementation on Competition and Training Performance in Elite Swimmer. Nutrients. 2012; 4:1441-1453.
  • Hill CA, Harris RC, Kim HJ, Harris BD, Sale C, Boobis LH, Kim CK, Wise JA. Influence of beta-alanine supplementation on skeletal muscle carnosine concentrations and high intensity cycling capacity. Amino Acids. 2007 Feb;32(2):225-33.
  • Hobson, R.; Saunders, B.; Ball, G.; Harris, R.; Sale, C. Effects of β-alanine supplementation on exercise performance: A meta-analysis. Amino Acids 2012, 43, 25–37.
  • Tallon MJ, Harris RC, Boobis LH, Fallowfield JL, Wise JA. The carnosine content of vastus lateralis is elevated in resistance-trained bodybuilders. J Strength Cond Res. 2005 Nov;19(4):725-9. PubMed PMID: 16287364.