Sunday, November 17, 2013

Beta Alanine Fails to HIIT Back: No Increased Training Effect in Response to Nine 4x4 Min HIIT Workouts W/ BA Preload, But Evidence in Favor of Chronic Supplementation

Contemporary scientific evidence suggest that you have to pick the right type of (short intense) exercise if you don't want your beta alanine supplement to end up as another "false starter" in your closet.
In the past couple of weeks beta alanine (BA) has gotten some bad press, here at the SuppVersity. While some conspiracy theorists may already have smelled a personal vendetta of a sodium bicarbonate advocate like myself against its 'high tech competitor', the actual reason for the negative, or at least not necessarily exciting news is the exercise specificity of beta alanine (BA) supplementation.

The most recent BA study from the  University of Bern and the Swiss Federal Institute of Sport in Switzerland and the Karolinska University Hospital in Sweden is yet another rather disappointing BA study to support my previous assertion that the benefits for the average gymrat are largely overblown.

What did the researchers do

As Gross et al. point out, the aim of their two-part intervention study was to alter the physiological systems discussed above in ways that could improve severe exercise performance. In that, their hypotheses were that
  1. If we look at the results of previous studies, it appears that the question, whether BA ↪ promotes or ↪ blunts the ergogenic effects of baking soda does also depend on the type of exercise.
    ... HIIT, by improving VO2max and VO2 kinetics, would enhance aerobic energy contribution during severe cycling exercise
  2. ... beta-alanine supplementation, by increasing intramuscular carnosine, would improve buffering capacity and reduce pH disturbance, or otherwise dampen muscle fatigue during severe cycling exercise; and 
  3. ... prior supplementation with beta-alanine would allow for greater training load and better recovery during HIIT,which would enhance benefits of training on physiological determinants of severe exercise performance. 
As a seasoned SuppVersity veteran you know about the profound training effect of high intensity (if you don't educate yourself). You will also know / have expected that the 38-day preload in the course of which the participants consumed either
  • * supplements were provided as 400-mg gel capsules and taken with the 3 main meals and before bed
    4 x 800mg/day "purified beta alanine"* (BA), or
  • 4 x 800mg/day maltedextrin (PLA),
would increase the intramuscular carnitine stores of the participants in the BA group. What you don't know, however, is whether the eight endurance, team, or combat sport athletes in the active study arm would also display lower serum pH levels, experience less fatigue, and record greater improvements in VO2max than the remaining nine subjects in the placebo arm of the study.

Let's take a look at the results

I guess, it doesn't make sense to keep you on the tenderhooks any longer, so let's see what happened  during and after the obligatory nine 4 x 4 minute interval HIIT sessions on a cycle ergometer (10 min warm-up; heart rate 90-95% of max; 3min light cycling between intervals).
Simply taking your beta alanine supplements with food increases the absorption of BA more effectively than fancy "time-release" caps or tablets | read more
Chronic vs. cyclic BA supplementation: It is an interesting side-finding of he study at hand that 9 HIIT sessions and a 7-day rest-period can reduce the carnosine overload in the vastus lateralis and vastus internus (the teardrop muscle) by statistically significant 6.5% and 12.2%, respectively. This would mean that a chronic high intensity overload can very well induce significant reductions in carnosine levels within less than a month. A workout fanatic who wants to keep his muscles supersaturated with carnosine on all 365 days of the year should thus not follow my previous suggestion to do 6-weeks on, 4-weeks off cycles. In view of the results of the study at hand, I will yet leave it to you to decide whether you feel this is actually worth the effort / money.
The sessions were performed as follows: Sessions 1-3, 1 day rest, sessions 4-7, one day rest, sessions 8-9; and all participants had been following their habitual training and nutrition regimen during the 38-day "preload".
Figure 1: Changes in VO2max, peak power output, max. blood lactate, and power at second ventilatory threshold in from baseline (pre) to post-supplementation (before HIIT) and from baseline (pre) to the end of the study (after HIIT +7-days)
If you read the text in Figure 1, you will be aware that the changes the scientists observed in response to the exercise regimen look impressive, but lack statistical significance. In the end, the results are thus way less exciting than the relative performance increases in the 10 ± 5% range would suggest.

It is difficult to say if the overall effect size is the reason that there were no significant inter-group differences. Since there were not differences at all (not even borderline or non-significant ones), it is however unlikely that a longer study duration and correspondingly more pronounced increases in VO2Max, peak power and co, as well as the likewise identical post workout glycogen synthesis and muscle fiber cross-sectional area would have yielded a significant advantage on part of the BA supplemented trainees. The fact that the increases in skeletal muscle buffering capacity reached significance only in the placebo group, would even support the exact opposite hypothesis, i.e. more pronounced long-term adaptive effects without beta alanine supplementation.
The 2012 meta-analysis by Hobson et al. demonstrated two things (a) BA produces predictable performance increases only in the 60-120s range and (b) the overall effect size is much smaller than what most people are (mis-)lead to believe, when they read the advertisements... ah "write-ups" on the Internet.
What do we make of these results? In view of the overall rather disappointing results, I am not sure if you feel that the 1.3% increase in aerobic activity and -5% decrease in O2 deficit is convincing enough to subscribe to idea that beta alanine powered carnosine loading is a viable strategy to improve the adaptive response to long(er)-duration interval training (here "longer" is 4-min).

In my humble opinion this is not the case. Not necessarily because I feel that BA is a supplemental non-starter, but rather in view of its exercise- / duration-specificity, of which Hobson et al. wrote in their 2012 meta-analysis that it restricts the usefulness of beta alanine to sports where the overall duration of high intensity muscular contractions is longer than 60s, but shorter than 240s. This is a pretty narrow margin and even within this "performance zone" the mean effect size of 2.85% does not come remotely close to what you'd expect to see when you read the boastful promises in the "write-ups" of the supplement industry.
References:
  • Hobson RM, Saunders B, Ball G, Harris RC, Sale C. Effects of β-alanine supplementation on exercise performance: a meta-analysis. Amino Acids. 2012 Jul;43(1):25-37.
  • Gross M, Boesch C, Bolliger CS, Norman B, Gustafsson T, Hoppeler H, Vogt M. Effects of beta-alanine supplementation and interval training on physiological determinants of severe exercise performance. Eur J Appl Physiol. 2013 Nov 9. [Epub ahead of print]