The absorption of orally supplied β-Alanine and its effect on muscle carnosine synthesis in human vastus lateralis

School of Sports, Exercise and Health Sciences, University College Chichester, West Sussex, Chichester, UK.
Amino Acids (Impact Factor: 3.29). 05/2006; 30(3):279-89. DOI: 10.1007/s00726-006-0299-9
Source: PubMed


Beta-alanine in blood-plasma when administered as A) histidine dipeptides (equivalent to 40 mg . kg(-1) bwt of beta-alanine) in chicken broth, or B) 10, C) 20 and D) 40 mg . kg(-1) bwt beta-alanine (CarnoSyn, NAI, USA), peaked at 428 +/- SE 66, 47 +/- 13, 374 +/- 68 and 833 +/- 43 microM. Concentrations regained baseline at 2 h. Carnosine was not detected in plasma with A) although traces of this and anserine were found in urine. Loss of beta-alanine in urine with B) to D) was <5%. Plasma taurine was increased by beta-alanine ingestion but this did not result in any increased loss via urine. Pharmacodynamics were further investigated with 3 x B) per day given for 15 d. Dietary supplementation with I) 3.2 and II) 6.4 g . d(-1) beta-alanine (as multiple doses of 400 or 800 mg) or III) L-carnosine (isomolar to II) for 4 w resulted in significant increases in muscle carnosine estimated at 42.1, 64.2 and 65.8%.

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    • "Thus, we could argue that during the 45-jump test anaerobic glycolysis and lactate accumulation were not connected to any major disturbance of buffering capacity , accumulation of lactate, or improved mitochondrial coupling. A possible explanation is that BA supplementation increased carnosine muscle content in subjects and that the proton-sequestering property of the carnosine molecule reduced the drop in muscle pH induced by the anaerobic glycolysis, improving performance (Harris et al. 2006). "
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    ABSTRACT: β-Alanine (BA) supplementation has become an ergogenic aid amongst competitive athletes to augment intramuscular carnosine content, leading to higher buffer capacity and exercise performance. We investigated 27 regularly trained young males and females who were randomly allocated either to placebo (PL) or BA ingestion for 8 weeks. Every single day, BA or PL (4.0-5.6 g day(-1)) supplements were ingested by participants and associated with a strong plyometric high-intensity training (two sessions per week during the 8 weeks). Before and after training, maximal jump heights were recorded during squat jump (SJ) and countermovement jump (CMJ) and an index of fatigue was recorded as a mean height of 45 consecutive CMJ. Blood lactate was measured at rest, after completing the fatigue test and every 5 min thereafter up to 30 min recovery. After plyometric training, SJ and CMJ were increased, respectively, by 8.8 and 6.4 % in PL group and 9.9 and 11.0 % in BA group (p < 0.01, no difference between groups). Blood lactate reached a maximal value of 9.4 ± 1.6 mmol l(-1) in PL group, and 10.3 ± 1.3 mmol l(-1) in BA group, with a slight better performance in the fatigue test (+8.6 %, p ≤ 0.01) for BA group as compared to PL group. To conclude, 2-month β-alanine supplementation resulted in a slight improvement of explosive force after 45 maximal consecutive jumps in young athletes. However, the practical adequacy of supplementation remains questionable in an active and healthy population.
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    • "Raising muscle carnosine concentrations in humans has been found to be relatively easy by means of chronic oral -alanine administration (Harris et al. 2006), whereas raising plasma carnosine levels seems very difficult in humans owing to the high and human-specific serum carnosinase activity (Everaert et al. 2012). "
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    • " et al . , 2009 ) . With 800 - mg doses ( 10 mg·kg −1 ) , Harris et al . ( 2006 ) reported " mild symptoms of flushing " in two out of four partici - pants , beginning within 20 min and lasting for up to 1 h . With a 1 . 6 - g dose , symptoms were recorded as " significant " in three of four participants ( Harris et al . , 2006 ) . Further work by Harris et al . ( 2006 ) has reported that a single β - alanine doses of 3 . 2 g ( 40 mg·kg −1 ) results in side effects that are perceived as " unpleasant " . The available literature suggests that the incidence and severity of the symptoms appears to follow in a dose - dependent fashion . The symp - toms observed in this study after the acute ingestion of 3"
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    Full-text · Article · Jan 2015 · European Journal of Sport Science
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