The effects of 10 weeks of resistance training combined with β-alanine supplementation on whole body strength, force production, muscular endurance and body composition

Abstract

Carnosine (Carn) occurs in high concentrations in skeletal muscle is a potent physico-chemical buffer of H+ over the physiological range. Recent research has demonstrated that 6.4 g x day(-1) of beta-alanine (beta-ala) can significantly increase skeletal muscle Carn concentrations (M-[Carn]) whilst the resultant change in buffering capacity has been shown to be paralleled by significant improvements in anaerobic and aerobic measures of exercise performance. Muscle carnosine increase has also been linked to increased work done during resistance training. Prior research has suggested that strength training may also increase M-[Carn] although this is disputed by other studies. The aim of this investigation is to assess the effect of 10 weeks resistance training on M-[Carn], and, secondly, to investigate if increased M-[Carn] brought about through beta-ala supplementation had a positive effect on training responses. Twenty-six Vietnamese sports science students completed the study. The subjects completed a 10-week resistance-training program whilst consuming 6.4 g x day(-1) of beta-ala (beta-ALG) or a matched dose of a placebo (PLG). Subjects were assessed prior to and after training for whole body strength, isokinetic force production, muscular endurance, body composition. beta-Alanine supplemented subjects increased M-[Carn] by 12.81 +/- 7.97 mmol x kg(-1) dry muscle whilst there was no change in PLG subjects. There was no significant effect of beta-ala supplementation on any of the exercise parameters measured, mass or % body fat. In conclusion, 10 weeks of resistance training alone did not change M-[Carn].

Muscle Carnosine Metabolism and β-Alanine Supplementation in Relation to Exercise and Training

“…In physical education students, the supplementation of 6.4 g . day -1 beta-alanine (10 weeks) did not have any additive effect compared to training alone on whole body strength, isokinetic force production, muscular endurance and body composition after 10 weeks of resistance training [75]. On the other hand Hoffman and colleagues [111] reported that collegiate football players, who are used to strength and power training, improved strength and body composition after 10 weeks of resistance training in a group consuming both beta-alanine and creatine compared to the placebo and/or creatine group.…”

“…Most other studies, however, do not report an increase in muscle carnosine content following different types of training. According to Kendrick et al [75], 10 weeks (4 sessions per week) of resistance training did not change the carnosine content of the vastus lateralis. Also in response to isokinetic knee extensor training [58;76], no carnosine loading is observed.…”

“…The experimental group reached a significantly higher training volume in the bench press exercise and a trend for all resistance exercise sessions, combined with a better subjective feeling. In addition to the differences in initial training levels of the subjects, the higher volume and the possible synergistic effect of beta-alanine with creatine in the study of Hoffman et al [111] could explain the inconsistency between these two comparable studies [75].…”

Relevance of allosteric conformations and homocarnosine concentration on carnosinase activity

“…Treatment with ß-alanine increased muscle carnosine concentrations (Kendrick et al 2008;Baguet et al 2009). Whereas there seems to be no positive effect of muscle carnosine loading on muscle strength (Kendrick et al 2008), we can conclude from the data reported by Baguet et al that carnosine is a stable compound in human skeletal muscle. A comparison of carnosine content between a group of elderly Korean males and young elite Korean swimmers showed no difference in muscle carnosine concentration (Kim 2009).…”

“…Treatment with carnosine significantly reduced infarct volume and improved neurological function in a mouse model of ischaemic stroke (Min et al 2008). Treatment with ß-alanine increased muscle carnosine concentrations (Kendrick et al 2008;Baguet et al 2009). Whereas there seems to be no positive effect of muscle carnosine loading on muscle strength (Kendrick et al 2008), we can conclude from the data reported by Baguet et al that carnosine is a stable compound in human skeletal muscle.…”