Effects of β-alanine supplementation on kickboxing-specific anaerobic performance, neuromuscular power, and strength endurance: A randomized, double-blind, placebo-controlled trial.
- 2026-05-13
- PloS one 21(5)
- Furkan Hasan Küçük
- Cebrail Gençoğlu
- Osman Ateş
- Jonatas Deivyson Reis Da Silva Duarte
- Dino Belošević
- Salih Çabuk
- Muhammet Raşit İnaç
- Süleyman Ulupınar
- Serhat Özbay
- PubMed: 42127019
- DOI: 10.1371/journal.pone.0346898
Study Design
- Type
- Randomized Controlled Trial (RCT)
- Sample size
- n = 14
- Population
- 28 trained male kickboxers
- Methods
- randomly assigned to BA (6.4 g·day⁻¹; n=14) or placebo (n=14) in a double-blind, placebo-controlled design
- Blinding
- Double-blind
- Duration
- 4 weeks
β-Alanine (BA) elevates skeletal muscle carnosine and may improve repeated high-intensity performance; however, evidence in kickboxing is limited. This study investigated the effects of 4-week BA supplementation on sport-specific kickboxing anaerobic performance, neuromuscular power, and strength endurance in trained male kickboxers. Twenty-eight athletes were randomly assigned to BA (6.4 g·day ⁻ ¹; n = 14) or placebo (n = 14) in a double-blind, placebo-controlled design. Pre- and post-intervention assessments included the Kickboxing Anaerobic Speed Test (KAST₁-₅, KASTbest, KASTtotal, Performance Decrement Index [PDI]), neuromuscular power (countermovement jump [CMJ], squat jump [SJ]), and strength endurance tests (push-up, pull-up). Baseline differences were tested via t-tests, effect sizes calculated according to Hedges' g formula. Group × time effects were analyzed using two-way repeated-measures ANOVA with partial eta squared (ηp²) effect sizes. Baseline measures were comparable (all p > 0.05). After supplementation, no significant group × time interactions emerged for CMJ (p = 0.148), SJ (p = 0.717), KAST₁-₅ (all p > 0.05), KASTbest (p = 0.071), or PDI (p = 0.454). However significant improvements were observed in the BA group for KASTtotal (F(1,26) = 14.49, p < 0.001, ηp² = 0.358), push-ups (F(1,26) = 5.89, p = 0.023, ηp² = 0.185), and pull-ups (F(1,26) = 9.79, p = 0.004, ηp² = 0.274). Four weeks of BA supplementation enhanced total anaerobic performance (KASTtotal) and upper-body strength endurance (push-up, pull-up), while no significant changes were observed in neuromuscular jump performance (CMJ, SJ). BA appears to be a practical ergogenic aid for improving repeated-effort and strength-endurance capacity in kickboxing. Clinical trial registration ClinicalTrials.gov (NCT07319052).
Research Insights
no significant group×time interactions emerged for KASTbest (p=0.071)
- Effect
- Neutral
- Effect size
- Small
- Dose
- 6.4 g·day⁻¹
significant improvements observed in the BA group for KASTtotal (F(1,26)=14.49, p<0.001, ηp²=0.358)
- Effect
- Beneficial
- Effect size
- Large
- Dose
- 6.4 g·day⁻¹
no significant group×time interactions emerged for CMJ (p=0.148)
- Effect
- Neutral
- Effect size
- Small
- Dose
- 6.4 g·day⁻¹
no significant group×time interactions emerged for PDI (p=0.454)
- Effect
- Neutral
- Effect size
- Small
- Dose
- 6.4 g·day⁻¹
significant improvements observed in the BA group for pull-ups (F(1,26)=9.79, p=0.004, ηp²=0.274)
- Effect
- Beneficial
- Effect size
- Large
- Dose
- 6.4 g·day⁻¹
significant improvements observed in the BA group for push-ups (F(1,26)=5.89, p=0.023, ηp²=0.185)
- Effect
- Beneficial
- Effect size
- Large
- Dose
- 6.4 g·day⁻¹
no significant group×time interactions emerged for KAST₁-₅ (all p>0.05)
- Effect
- Neutral
- Effect size
- Small
- Dose
- 6.4 g·day⁻¹
no significant group×time interactions emerged for SJ (p=0.717)
- Effect
- Neutral
- Effect size
- Small
- Dose
- 6.4 g·day⁻¹