Beta-alanine (Carnosyn™) supplementation in elderly subjects (60–80 years): effects on muscle carnosine content and physical capacity

Abstract

The aim of this study was to investigate the effects of beta-alanine supplementation on exercise capacity and the muscle carnosine content in elderly subjects. Eighteen healthy elderly subjects (60–80 years, 10 female and 4 male) were randomly assigned to receive either beta-alanine (BA, n = 12) or placebo (PL, n = 6) for 12 weeks. The BA group received 3.2 g of beta-alanine per day (2 × 800 mg sustained-release Carnosyn™ tablets, given 2 times per day). The PL group received 2 × (2 × 800 mg) of a matched placebo. At baseline (PRE) and after 12 weeks (POST-12) of supplementation, assessments were made of the muscle carnosine content, anaerobic exercise capacity, muscle function, quality of life, physical activity and food intake. A significant increase in the muscle carnosine content of the gastrocnemius muscle was shown in the BA group (+85.4%) when compared with the PL group (+7.2%) (p = 0.004; ES: 1.21). The time-to-exhaustion in the constant-load submaximal test (i.e., TLIM) was significantly improved (p = 0.05; ES: 1.71) in the BA group (+36.5%) versus the PL group (+8.6%). Similarly, time-to-exhaustion in the incremental test was also significantly increased (p = 0.04; ES 1.03) following beta-alanine supplementation (+12.2%) when compared with placebo (+0.1%). Significant positive correlations were also shown between the relative change in the muscle carnosine content and the relative change in the time-to-exhaustion in the TLIM test (r = 0.62; p = 0.01) and in the incremental test (r = 0.48; p = 0.02). In summary, the current data indicate for the first time, that beta-alanine supplementation is effective in increasing the muscle carnosine content in healthy elderly subjects, with subsequent improvement in their exercise capacity.

Doubling of Muscle Carnosine Concentration Does Not Improve Laboratory 1-Hr Cycling Time-Trial Performance

“…3 A key finding in this study is the largest ever--reported relative increase in muscle carnosine 4 concentration following beta--alanine supplementation. So far, the highest reported relative 5 increases in muscle carnosine following chronic beta--alanine supplementation were 80--85% 6 following 10--12 weeks (Del Favero et al, 2012;Hill et al, 2007). We now document an increase of 7 ~1 50% after only 6 weeks of supplementation.…”

Scientific Opinion on the substantiation of a health claim related to beta-alanine and increase in physical performance during short-duration, high-intensity exercise pursuant to Article 13(5) of Regulation (EC) No 1924/2006

“…As a result, the applicant identified four human intervention studies which investigated the effect of beta-alanine on physical performance during short-term, high intensity exercise and also reported on muscle carnosine concentrations as being pertinent to the claim (Derave et al, 2007;Hill et al, 2007;Baguet et al, 2010;Del Favero et al, 2012). EFSA informed the applicant that all available scientific evidence is used by EFSA in the scientific evaluation of the claim and therefore all studies on the effects of beta-alanine on physical performance (claimed effect) which did and did not report on muscle carnosine stores (proposed mechanism for the effect) will be used.…”

“…The Panel notes that eight of these studies (Stout et al, , 2007Zoeller et al, 2006;Hill et al, 2007;Salle et al, 2011;Smith et al, 2011;Del Favero et al, 2012;Smith-Ryan et al, 2012) assessed measures of physical capacity (e.g. time to exhaustion and/or total work done and/or physical working capacity at fatigue threshold) in the context of time unlimited physical activities and did not include any measures of physical performance.…”

β–alanine: performance effects, usage and side effects

“…There was a moderate positive relationship The incidence rate of side effects following β-alanine supplementation has been inconsistently reported in previous 'β-alanine' studies. Several studies have reported no side effects at all following doses of 800 mg to 1600 mg [52,110,171,175]. In contrast, Harris et al [10] reported "significant" symptoms in three out of their four male participants who had an average body mass of 80.2 ± 17.1 kg and supplemented with a 20 mg·kgBM -1 dose of β-alanine.…”

“…Stegen et al [108] extrapolated the data from four studies that showed both an increase in M-Carn levels and an increase in exercise performance [52,72,109,110].…”