Abstract
The aim of the present study was to assess the effects of beta-alanine supplementation on muscle strength and thickness. Nineteen resistance-trained men (age: 27.3 ± 5.5 years; height: 178 ± 10 cm; body mass: 83.4 ± 9.7 kg; training experience: 5.9 ± 3.9 years) were allocated to one of the following groups: Beta-alanine (BA) (6.4 g/day of beta-alanine) or Placebo (PLA) (6.4 g/day of maltodextrin). Subjects completed 4 resistance training sessions per week for 8 weeks. The following assessments were performed before and after intervention periods: 1 repetition maximum (1RM) and 60%1RM tests in the bench press (60%1RM(BENCH)) and back squat (60%1RM(SQUAT)) exercises; muscle thickness assessment of biceps brachialis (MT(BB)), triceps brachialis (MT(TB))(,) and vastus lateralis (MT(VL)) by ultrasonography. No significant difference between groups was observed for the absolute increase (pre-post intervention) in the 1RM(BENCH) (mean difference = 0.8 kg; p = 0.679), 1RM(SQUAT) (mean difference = 0.1 kg; p = 0.992), MT(BB) (mean difference = 0.7 mm; p = 0.637), MT(TB) (mean difference = 1.4 mm; p = 0.282), MT(VL) (mean difference = 1.6 mm; p = 0.311), 60%1RM(BENCH) (mean difference = 0.5 repetitions; p = 0.670) and 60%1RM(SQUAT) (mean difference = 0.7 repetitions; p = 0.690). In conclusion, the 8-week training period induced significant strength and morphological responses. However, the addition of beta-alanine supplementation did not enhance these adaptive outcomes.