2.1. Zwiększenie wydolności fizycznej podczas krótkotrwałych ćwiczeń o wysokiej intensywności (ID 436, 1453, 1454, 1459)

The claimed effects are “increases muscle carnosine, the intracellular buffering agent proposed to be responsible for the beneficial effect on short-duration high intensity exercise”, “beta-alanine improves exercise performance”, “beta-alanine increases muscle buffering capacity” and “improves cycling performance”. The Panel assumes that the target population is active individuals in the general population.
In the context of the proposed wordings, the Panel assumes that the claimed effect refers to the increase in physical performance during short-term high-intensity exercise induced by an increase in muscle buffering capacity. Performance relates to the ability of completing a certain task (e.g. running a certain distance) as fast as possible.
The Panel considers that an increase in physical performance during short-term high-intensity exercise is a beneficial physiological effect.

2.2. Wzrost czasu do wyczerpania (ID 437, 438, 439, 683, 1452, 1455, 1456, 1459)

The claimed effects are “increasing time to exhaustion”, “increasing training volume and work”, “physical performance”, “beta-alanine reduces muscle fatigue”, “increasing exercise thresholds”, “beta-alanine increases muscle buffering capacity” and “beta-alanine improves muscle work capacity”. The Panel assumes that the target population is active individuals in the general population.
In the context of the proposed wordings, the Panel assumes that the claimed effect refers to the increase in time to exhaustion by improving muscle resistance to fatigue through an increase in muscle buffering capacity.
The Panel considers that an increase in time to exhaustion is a beneficial physiological effect.

2.3. Zwiększenie ilości karnozyny w mięśniach (ID 1457, 1458)

The claimed effects are “beta-alanine increases muscle carnosine stores” and “beta-alanine increases muscle carnosine stores in fast twitch muscle fibres”. The Panel assumes that the target population is the general population.
The Panel considers that the evidence provided does not establish that an increase in muscle carnosine stores is a beneficial physiological effect.
The Panel concludes that a cause and effect relationship has not been established between the consumption of beta-alanine and a beneficial physiological effect related to an increase in muscle carnosine stores.

3.1. Zwiększenie wydolności fizycznej podczas krótkotrwałych ćwiczeń o wysokiej intensywności (ID 436, 1453, 1454, 1459)

Most of the references provided for the scientific substantiation of this claim did not address the effects of beta-alanine consumption on measures of physical performance but rather on other outcomes (e.g. carnosine stores). In addition, two abstracts were submitted in which the information provided regarding the study design, methodology and statistical analyses was insufficient for a complete scientific evaluation (Hill et al., 2005; Kim et al., 2007). The Panel considers that no conclusions can be drawn from these references for the scientific substantiation of the claimed effect.
Three randomised, placebo controlled, double blind intervention studies in humans assessing the effects of beta-alanine on different outcomes (physical working capacity at neuromuscular fatigue threshold, ventilatory threshold, VO2max, time-to-exhaustion, total work executed) in relation to the practice of short-duration, high-intensity exercise were provided (Stout et al., 2006, 2007; Hill et al., 2007). However, the Panel notes that physical performance was not assessed in any of the studies and considers that no conclusions can be drawn from these studies for the scientific substantiation of the claimed effect.
The Panel concludes that a cause and effect relationship has not been established between the consumption of beta-alanine and an increase in physical performance during short-term high-intensity exercise.

3.2. Wzrost czasu do wyczerpania (ID 437, 438, 439, 683, 1452, 1455, 1456, 1459)

Most of the references provided for the scientific substantiation of this claim did not address the effects of beta-alanine consumption on measures of time to exhaustion but rather on other outcomes (e.g. carnosine stores). In addition, two abstracts were submitted in which the information provided regarding the study design, methodology and statistical analyses was insufficient for a complete scientific evaluation (Hill et al., 2005; Kim et al., 2007). The Panel considers that no conclusions can be drawn from these references for the scientific substantiation of the claimed effect.
Three randomised, placebo controlled, double blind intervention studies in humans assessing the effects of beta-alanine on different outcomes in relation to the practice of short duration, high- intensity exercise have been provided (Stout et al., 2006, 2007; Hill et al., 2007).
Stout et al. (2006) investigated the effects of beta-alanine supplementation on physical working capacity at neuromuscular fatigue threshold in young men in a randomised, double-blinded, placebo- controlled study. Subjects were randomised to consume 2 to 4 times daily either 34 g of dextrose (placebo, n=13) or 34 g dextrose plus 1.6 g beta-alanine (beta-alanine group, n=12) for 28 days. Before and after the supplementation period, a continuous incremental bike test was performed while a surface electromyographic signal was recorded from the vastus lateralis muscle to determine physical working capacity at neuromuscular fatigue threshold, which was determined by a test which uses the relationship between electromyographic amplitude and fatigue during submaximal cycling to identify the highest power output that corresponds to the onset of neuromuscular fatigue. The Panel notes that physical working capacity at neuromuscular fatigue threshold only provides information about the intensity/workload achieved at the fatigue threshold, but does not provide information about the time to exhaustion. A more recent publication in relation to the same study (not provided in the consolidated list) reports that no group effect was observed in time to exhaustion in the biking test after beta-alanine supplementation compared to placebo (Zoeller et al., 2007).
In a randomised, double-blinded, placebo-controlled intervention study, Stout et al. (2007) investigated the effects of beta-alanine supplementation on physical working capacity at fatigue threshold, ventilatory threshold, VO2max and time to exhaustion. A total of 22 young women were randomly assigned to consume either beta-alanine (3.2 to 6.4 g per day, n=11) or maltodextrin (placebo, n=11) for 28 days. Exercise tests consisted of a continuous graded biking test, starting at 40
Watt and increased by 20 Watt every 3 minutes until exhaustion ( 1100 seconds). No significant differences between groups were observed in time to exhaustion.
In a randomised, placebo controlled, double-blinded intervention study, Hill et al. (2007) investigated the effects of beta-alanine supplementation on total work executed during a biking test. Beta-alanine was administered each day in eight divided doses for four weeks (n=5) or 10 weeks (n=8), with the total daily dose increasing during the first four weeks from 4.0 to 6.4 g per day. Twelve subjects received maltodextrin as placebo. Beta-alanine supplementation resulted in a significant increase in total work done during the biking test at high intensity (110 % of maximum power) compared to placebo, which is directly proportional to time to exhaustion for exercises performed at fixed intensity. The Panel notes the small number of subjects recruited in this study.
In weighing the evidence, the Panel took into account that two of the three small intervention studies in humans showed no effect of beta-alanine supplementation on the time to exhaustion compared to placebo, and that the evidence provided is limited and inconsistent.
The Panel concludes that a cause and effect relationship has not been established between the consumption of beta-alanine and an increase in time to exhaustion.