J Appl Physiol. 2010 Oct;109(4):1096-101. Epub 2010 Jul 29.
Important role of muscle carnosine in rowing performance.

Baguet A, Bourgois J, Vanhee L, Achten E, Derave W.

Dept. of Movement and Sports Sciences, Ghent Univ., Watersportlaan 2, B-9000 Ghent, Belgium. Wim.derave@ugent.be.
Abstract

The role of the presence of carnosine (β-alanyl-l-histidine) in millimolar concentrations in human skeletal muscle is poorly understood.

Chronic oral β-alanine supplementation is shown to elevate muscle carnosine content and improve anaerobic exercise performance during some laboratory tests, mainly in the untrained.

It remains to be determined whether carnosine loading can improve single competition-like events in elite athletes. The aims of the present study were to investigate if performance is related to the muscle carnosine content and if β-alanine supplementation improves performance in highly trained rowers.

Eighteen Belgian elite rowers were supplemented for 7 wk with either placebo or β-alanine (5 g/day). Before and following supplementation, muscle carnosine content in soleus and gastrocnemius medialis was measured by proton magnetic resonance spectroscopy ((1)H-MRS) and the performance was evaluated in a 2,000-m ergometer test.

At baseline, there was a strong positive correlation between 100-, 500-, 2,000-, and 6,000-m speed and muscle carnosine content. After β-alanine supplementation, the carnosine content increased by 45.3% in soleus and 28.2% in gastrocnemius.

Following supplementation, the β-alanine group was 4.3 s faster than the placebo group, whereas before supplementation they were 0.3 s slower (P = 0.07). Muscle carnosine elevation was positively correlated to 2,000-m performance enhancement (P = 0.042 and r = 0.498).

It can be concluded that the positive correlation between baseline muscle carnosine levels and rowing performance and the positive correlation between changes in muscle carnosine and performance improvement suggest that muscle carnosine is a new determinant of rowing performance.[/I]

Med Sci Sports Exerc. 2010 Jun;42(6):1162-73.
Role of beta-alanine supplementation on muscle carnosine and exercise performance.

Artioli GG, Gualano B, Smith A, Stout J, Lancha AH Jr.

Laboratory of Applied Nutrition and Metabolism, School of Physical Education and Sports, University of São Paulo, São Paulo, Brazil. artioli@usp.br
Abstract

In this narrative review, we present and discuss the current knowledge available on carnosine and beta-alanine metabolism as well as the effects of beta-alanine supplementation on exercise performance. Intramuscular acidosis has been attributed to be one of the main causes of fatigue during intense exercise. Carnosine has been shown to play a significant role in muscle pH regulation. Carnosine is synthesized in skeletal muscle from the amino acids l-histidine and beta-alanine. The rate-limiting factor of carnosine synthesis is beta-alanine availability. Supplementation with beta-alanine has been shown to increase muscle carnosine content and therefore total muscle buffer capacity, with the potential to elicit improvements in physical performance during high-intensity exercise. Studies on beta-alanine supplementation and exercise performance have demonstrated improvements in performance during multiple bouts of high-intensity exercise and in single bouts of exercise lasting more than 60 s. Similarly, beta-alanine supplementation has been shown to delay the onset of neuromuscular fatigue. Although beta-alanine does not improve maximal strength or VO2max, some aspects of endurance performance, such as anaerobic threshold and time to exhaustion, can be enhanced. Symptoms of paresthesia may be observed if a single dose higher than 800 mg is ingested. The symptoms, however, are transient and related to the increase in plasma concentration. They can be prevented by using controlled release capsules and smaller dosing strategies. No important side effect was related to the use of this amino acid so far. In conclusion, beta-alanine supplementation seems to be a safe nutritional strategy capable of improving high-intensity anaerobic performance.

Eur J Appl Physiol. 2010 Feb;108(3):495-503. Epub 2009 Oct 16.
Beta-alanine supplementation reduces acidosis but not oxygen uptake response during high-intensity cycling exercise.

Baguet A, Koppo K, Pottier A, Derave W.

Department of Movement and Sports Sciences, Ghent University, Ghent, Belgium.
Abstract

The oral ingestion of beta-alanine, the rate-limiting precursor in carnosine synthesis, has been shown to elevate the muscle carnosine content. Carnosine is thought to act as a physiologically relevant pH buffer during exercise but direct evidence is lacking. Acidosis has been hypothesised to influence oxygen uptake kinetics during high-intensity exercise. The present study aimed to investigate whether oral beta-alanine supplementation could reduce acidosis during high-intensity cycling and thereby affect oxygen uptake kinetics. 14 male physical education students participated in this placebo-controlled, double-blind study. Subjects were supplemented orally for 4 weeks with 4.8 g/day placebo or beta-alanine. Before and after supplementation, subjects performed a 6-min cycling exercise bout at an intensity of 50% of the difference between ventilatory threshold (VT) and VO(2peak). Capillary blood samples were taken for determination of pH, lactate, bicarbonate and base excess, and pulmonary oxygen uptake kinetics were determined with a bi-exponential model fitted to the averaged breath-by-breath data of three repetitions. Exercise-induced acidosis was significantly reduced following beta-alanine supplementation compared to placebo, without affecting blood lactate and bicarbonate concentrations. The time delay of the fast component (Td(1)) of the oxygen uptake kinetics was significantly reduced following beta-alanine supplementation compared to placebo, although this did not reduce oxygen deficit. The parameters of the slow component did not differ between groups. These results indicate that chronic beta-alanine supplementation, which presumably increased muscle carnosine content, can attenuate the fall in blood pH during high-intensity exercise. This may contribute to the ergogenic effect of the supplement found in some exercise modes.

Med Sci Sports Exerc. 2009 Apr;41(4):898-903.
Beta-alanine improves sprint performance in endurance cycling.

Van Thienen R, Van Proeyen K, Vanden Eynde B, Puype J, Lefere T, Hespel P.

Department of Biomedical Kinesiology, Research Centre for Exercise and Health, Katholieke Universiteit Leuven, Leuven, Belgium.

Abstract

PURPOSE: Recent research has shown that chronic dietary beta-alanine (betaALA) supplementation increases muscle carnosine content, which is associated with better performance in short (1-2 min) maximal exercise. Success in endurance competitions often depends on a final sprint. However, whether betaALA can be ergogenic in sprint performance at the end of an endurance competition is at present unknown. Therefore, we investigated the effect of 8-wk betaALA administration in moderately to well-trained cyclists on sprint performance at the end of a simulated endurance cycling race.

METHODS: A double-blind study was performed, which consisted of two experimental test sessions interspersed by an 8-wk betaALA (2-4 g.d; n = 9) or matched placebo (PL; n = 8) supplementation period. In the pretesting and the posttesting, subjects performed a 10-min time trial and a 30-s isokinetic sprint (100 rpm) after a 110-min simulated cycling race. Capillary blood samples were collected for determination of blood lactate concentration and pH.

RESULTS: Mean power output during the time trial was approximately 300 W and was similar between PL and betaALA during either the pretesting or the posttesting. However, compared with PL, during the final sprint after the time trial, betaALA on average increased peak power output by 11.4% (95% confidence interval = +7.8 to +14.9%, P = 0.0001), whereas mean power output increased by 5.0% (95% confidence interval = +2.0 to +8.1%, P = 0.005). Blood lactate and pH values were similar between groups at any time.

CONCLUSION: Oral betaALA supplementation can significantly enhance sprint performance at the end of an exhaustive endurance exercise bout.

Beta-Alanine gör mer än bara kliar, de fungerar ju med
Intressant läsning.

Har du läst om något nytt om de kommit överänns om varför det kliar i kroppen?

Sist jag läste om det så var de inte överänns om exakt varför stickingarna uppkommer

Ursprungligen postat av Tim

Beta-Alanine gör mer än bara kliar, de fungerar ju med
Intressant läsning.

Har du läst om något nytt om de kommit överänns om varför det kliar i kroppen?

Sist jag läste om det så var de inte överänns om exakt varför stickingarna uppkommer

nja fortfarande oklart mekanismerna. det är dock ungefär samma mekanismer som när ex en fot somnar och det blir stickningar.

mer och mer stöd för beta alanin

J Strength Cond Res. 2011 Jul;25(7):1804-15.
Effects of β-Alanine Supplementation on Performance and Body Composition in Collegiate Wrestlers and Football Players.
Kern BD, Robinson TL.
Source

Human Performance and Physical Education Department, Adams State College, Alamosa, Colorado.

Abstract

Kern, BD and Robinson, TL. Effects of β-alanine supplementation on performance and body composition in collegiate wrestlers and football players. J Strength Cond Res 25(7): 1804-1815, 2011-The purpose of this study was to examine the effectiveness of β-alanine as an ergogenic aid in tests of anaerobic power output after 8 weeks of high-intensity interval, repeated sprint, and resistance training in previously trained collegiate wrestlers (WR) and football (FB) players. Twenty-two college WRs (19.9 ± 1.9 years, age ± SD) and 15 college FB players (18.6 ± 1.5 years) participated in this double-blind, placebo-controlled study. Each subject ingested either 4 g·d β-alanine or placebo in powdered capsule form. Subjects were tested pre and posttreatment in timed 300-yd shuttle, 90° flexed-arm hang (FAH), body composition, and blood lactate after 300-yd shuttle. Although not statistically significant (p > 0.05) subjects taking β-alanine achieved more desirable results on all tests compared to those on placebo. Performance improvements were greatest in the FB supplement group, decreasing 300 shuttle time by 1.1 seconds (vs. 0.4-second placebo) and increasing FAH (3.0 vs. 0.39 seconds). The wrestlers, both placebo and supplement, lost weight (as was the goal, i.e., weight bracket allowance); however, the supplement group increased lean mass by 1.1 lb, whereas the placebo group lost lean mass (-0.98 lb). Both FB groups gained weight; however, the supplement group gained an average 2.1-lb lean mass compared to 1.1 lb for placebo. β-Alanine appears to have the ability to augment performance and stimulate lean mass accrual in a short amount of time (8 weeks) in previously trained athletes. Training regimen may have an effect on the degree of benefit from β-alanine supplementation.

Well this is very well written article posted by you and i enjoyed every time to read this.