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Background and Objectives: One of the important factors in comparative athletes, especially swimmers, is respiratory function and respiration regulation during training and competition. The purpose of this study was to investigate the effect of 14 days of beta-alanine supplementation on first and second ventilatory threshold of the male swimmers.
Materials and Methods: Fourteen male swimmers were randomly divided into two groups, including supplementation (S) (age, 30.67 ± 6.34 years and BMI, 23.71 ± 2.28 kg/m²) and placebo (P) (age, 32.63 ± 10.26 years and BMI, 25.16 ± 2.51 kg/m²). The supplementation group took beta-alanine 2-3 g∙day^-1 in first week and 4-6 g∙day^-1 in second week whereas the control group took dextrose for two weeks instead but in same way. The respiratory indices of subjects were measured using cardio pulmonary exercise testing. Independent sample t test and paired-sample t test was used to compare the outcomes between and within groups respectively. The significance level was assumed as 95% for all cases (p<0.05).
Results: The results showed that β-alanine supplementation increased first and second ventilatory threshold (VT₁ and VT₂ respectively) in S group (p≤0.05). However, there was no significant difference between groups for VT₂.
Conclusions: Two weeks of beta-alanine supplementation with a dose of 2-6 grams per day provides a sufficient stimulus to improve the competitive ability of swimmers.