Beta-alanine (BA) is a popular supplement known for its potential ergogenic effects, particularly in high-intensity exercise. This randomized controlled trial aimed to explore the impact of BA supplementation on isotonic strength endurance performance during drop-set and bi-set resistance exercises among resistance-trained individuals.
The study involved 22 young resistance-trained men and women who were randomly assigned to either a BA group (6.4 g·day -1) or a placebo group (maltodextrin). After a familiarization period, participants underwent maximal strength (1-RM) and strength endurance tests. The primary outcomes measured were the total number of repetitions completed during drop-set and bi-set protocols, as well as psychological responses such as perceived exertion, motivation, and affect.
Results indicated that BA supplementation led to a significant increase in the total number of repetitions during both drop-set (+17.3%, effect size [ES] = 0.74, p = 0.007) and bi-set (+18.2%, ES = 0.98, p < 0.0001) protocols. In contrast, the placebo group showed no significant changes in performance (drop-set: -0.98%, ES = -0.06, p = 0.988; bi-set: +5.6%, ES = 0.01, p = 0.406).
Interestingly, while perceived exertion increased across sets during both exercise protocols (both p < 0.0001), there were no significant differences between the BA and placebo groups (both p > 0.05). Other psychological responses remained unaffected by the supplementation.
This study provides evidence that four weeks of BA supplementation can enhance isotonic strength endurance performance in resistance-trained individuals without affecting psychological responses during high-intensity resistance training.
What this study does not show
This study does not demonstrate the long-term effects of beta-alanine supplementation beyond the four-week period or its impact on other populations outside of resistance-trained individuals.
Evidence scorecard
- Analytic validity: established
- Clinical validity: established
- Clinical utility: established
The evidence class for this study is human_rct.