Beta-alanine has become a “must-have” supplement for many athletes, but does the science support the hype? Its inclusion as one of five performance-enhancing supplements with enough evidence to support its use in the International Olympic Committee’s recent consensus statement suggests it does. But what is beta-alanine, what does it do and in what situations might someone benefit this popular supplement?
The compound of interest in the body is carnosine, a dipeptide made up of the amino acids, histidine and beta-alanine. It is predominantly found in muscle which suggests it plays an important role during exercise. Carnosine can perform several physiological roles, although its function as a muscle buffer is most widely accepted as its predominant role during high-intensity exercise. This means that it can buffer the hydrogen ions (H+) that are generated during anaerobic glycolysis; these H+ contribute to muscle acidosis which can lead to muscle fatigue.
Therefore, increasing the muscle carnosine content can improve muscle pH regulation, which could lead to performance improvements during exercise that is limited by the accumulation of these H+
We know that beta-alanine is the rate-limiting factor in muscle carnosine synthesis, hence why we only supplement with this amino acid. The pioneering study of Prof. Roger Harris showed that chronic supplementation of 4 weeks with beta-alanine can increase muscle carnosine content (Harris et al., 2006), with almost all subsequent studies showing increases across individuals with between 2 and 24 weeks of supplementation between 3.2 and 6.4 g/day.
We performed a meta-analysis of all the evidence on beta-alanine supplementation on exercise available up until 2017 and showed that, on average, beta-alanine does lead to moderate improvements in exercise capacity and performance (Saunders et al., 2017). However, a couple of factors may modify this response, the most important being the duration of the exercise you undertake. Our results suggest that high-intensity exercise lasting between 30 s and 10 min is the timeframe most likely to benefit from beta-alanine supplementation. This includes, but is not limited to, sports such as 100 and 200 m swimming, 4-km time-trial cycling, 2000 m rowing and 800 m running. Exercise less than 30 s is not of sufficient duration to be affected by muscle acidosis, while endurance exercise is also less likely to be affected due to its more aerobic nature. That being said, it is possible that short periods of high-intensity activity performed throughout longer duration exercise may be improved with beta-alanine, such as a sprint finish at the end of a prolonged cycling race.
Importantly, it must be noted that we showed the more trained the individual, the smaller the effect beta-alanine is likely to have. This is possibly due to less room for improvement in already trained individuals. Nonetheless, it is worth considering that these gains are more valuable for athletes as it may translate into worthwhile improvements in competition. Medal rankings in several Olympic sports are separated by less than 1% while sprint finishes in cycling are separated by less than 1% while spirant finished are separated by thousandths of a second.
Is it safe?
So, it can increase muscle carnosine and improve performance, but is it safe to use? The overwhelming evidence suggests it is, and a recent meta-analytic summary of the available data concluded that beta-alanine can safely be consumed by health individuals in doses of up to 6.4 g/day up to 24 weeks (Dolan et al., 2019). However, many users will know that there is a common side-effect which feels like an itchy or tingling sensation on the skin shortly after taking the supplement. This sensation, which is termed paraesthesia, is related to a rapid increase of beta-alanine in the blood which subsides within 60-90 minutes and has no long-term health effects.
It tingles, so it works.....
While some common beliefs are that these sensations mean the supplement is working, the only acute effect this might have is as a placebo. It's surprising the number of individuals who find this sensation to be pleasant and believe it can help their workout but, since only chronic beta-alanine ingestion leads to changes in muscle carnosine content which may improve exercise, maybe it’s just better to put down that beta-alanine-containing pre-workout and save yourself some cash!
Which leads us into the final detail of how to take beta-alanine to maximise the likelihood of an exercise benefit. Recommended doses would be 3.2 to 6.4 g/day, with individual doses of 0.8-1.6 g every 3-4 h throughout the day to avoid paraesthesia. Unless, of course, that’s what you’re in to. Ooh it tingles!
DOLAN, E., SWINTON, P. A., PAINELLI, V. S., STEPHENS HEMINGWAY, B., MAZZOLANI, B., INFANTE SMAIRA, F., SAUNDERS, B., ARTIOLI, G. G. & GUALANO, B. 2019. A Systematic Risk Assessment and Meta-Analysis on the Use of Oral beta-Alanine Supplementation. Adv Nutr.
HARRIS, R. C., TALLON, M. J., DUNNETT, M., BOOBIS, L., COAKLEY, J., KIM, H. J., FALLOWFIELD, J. L., HILL, C. A., SALE, C. & WISE, J. A. 2006. The absorption of orally supplied beta-alanine and its effect on muscle carnosine synthesis in human vastus lateralis. Amino Acids,30,279-289.
SAUNDERS, B., ELLIOTT-SALE, K., ARTIOLI, G. G., SWINTON, P. A., DOLAN, E., ROSCHEL, H., SALE, C. & GUALANO, B. 2017. beta-alanine supplementation to improve exercise capacity and performance: a systematic review and meta-analysis. Br J Sports Med,51,658-669.
*Bryan Saunders has previously received a scholarship from Natural Alternatives International (NAI), San Marcos, California to undertake a study on beta-alanine. NAI has also provided free beta-alanine supplements for several original studies conducted by Dr Saunders, but NAI has never had any input into study design, interpretation or dissemination of results.