When performing high-intensity exercise, especially when the so-called "anaerobic" pathway is stimulated, the accumulation of metabolites or waste products such as hydrogen ions (H+) is a limiting factor (which occurs together with lactate production). That accumulation of hydrogen ions can lower our pH, increasing acidity and making it harder for muscle to contract. To avoid this decrease in pH we have different physiological buffers in our body, one of the best known being the bicarbonate buffer. Similarly, muscle carnosine also acts as a buffer against the decrease in intramuscular pH.
Beta-Alanine supplementation has been shown to increase intramuscular carnosine levels. For example, one study found that taking 3.2 g/day of Beta-Alanine increased carnosine levels by about 50% above baseline. In addition, after continuing with a maintenance phase taking only 1.2 g/day for 6 weeks, carnosine levels remained 30-50% above baseline levels (Stegen et al. 2014). Therefore, taking beta-alanine could be effective in increasing the body's buffer capacity, thus improving performance, especially in high-intensity exercise (those in which there is a greater decrease in pH).
In order to evaluate the ergogenic potential of this supplement, a recent meta-analysis published in the prestigious British Journal of Sports Medicine analyzed a total of 40 studies and almost 1500 participants. The results showed that beta-alanine consumption significantly improves athletic performance, especially in exercises between 1 and 10 minutes (Saunders et al. 2017). These results thus confirmed the previous findings of another meta-analysis published years earlier when the number of studies was even smaller, in which an average improvement in performance of approximately 3% was described (Hobson et al. 2012).
In the specific cases in which beta-alanine supplementation has been shown to be effective, we can refer to studies of great interest to most endurance athletes. For example, a recently published study (Santana et al. 2018) shows that taking beta-alanine (5 g/day for 23 days) decreases the time to complete a 10 km race to a greater extent than taking placebo (those who took beta-alanine improved their mark by more than 2 and a half minutes, while those who took placebo did so in just under a minute). On the other hand, one study (Van Thienen et al. 2009) evaluated the effect of taking beta-alanine (2-4 g/day for 8 weeks) on a 10-minute time trial and a final sprint of 30 seconds performed in fatigue (after a simulated 110 km race). The results showed that, although the power achieved during the time trial was similar in those who took beta-alanine and those who took placebo (~300W), beta-alanine increased peak and average power during the final sprint by 11 and 5%, respectively.
Therefore, beta-alanine supplementation has been shown to be effective in increasing levels of muscle carnosine, a natural physiological buffer that prevents the pH drop that occurs with high-intensity exercise. In addition, ample evidence supports the ergogenic potential of this supplement, especially for high-intensity exercise (1-10 minutes). These results are of great interest both for short-term sports and for those in which, despite being of long duration, they include moments of great intensity (e.g. a cycling stage).
References
- Hobson RM, Saunders B, Ball G, et al (2012) Effects of β-alanine supplementation on exercise performance: A meta-analysis. Amino Acids 43:25–37. doi: 10.1007/s00726-011-1200-z
- Santana JO, de Freitas MC, dos Santos DM, et al (2018) Beta-Alanine Supplementation Improved 10-km Running Time Trial in Physically Active Adults. Front Physiol 9:1–6. doi: 10.3389/fphys.2018.01105
- Saunders B, Elliott-Sale K, Artioli GG, et al (2017) β-Alanine supplementation to improve exercise capacity and performance: A systematic review and meta-Analysis. Br J Sports Med 51:658–669. doi: 10.1136/bjsports-2016-096396
- Stegen S, Bex T, Vervaet C, et al (2014) β-Alanine dose for maintaining moderately elevated muscle carnosine levels. Med Sci Sports Exerc 46:1426–1432. doi: 10.1249/MSS.0000000000000248
- Van Thienen R, Van Proeyen K, Eynde B Vanden, et al (2009) β-Alanine improves sprint performance in endurance cycling. Med Sci Sports Exerc 41:898–903. doi: 10.1249/MSS.0b013e31818db708
AUTHOR
Pedro Valenzuela
Researcher in the Physiology Unit of the University of Alcalá and in the Performance Control Unit at the Sports Medicine Center (AEPSAD, CAR of Madrid).
Web: www.fissac.com
