β-Alanine for Kickboxing Anaerobic Performance

NCT07319052 | Completed

• 2 other identifiers: ETU-BETAALANINE-202506/5/21.04.2025
• Study Type: interventional
• Target: 28
• Locations: 1 country
• Sites: 1

Brief Summary

This randomized, double-blind, placebo-controlled parallel-group trial will evaluate whether four weeks of β-alanine (BA) supplementation improves sport-specific anaerobic performance, neuromuscular power, and strength endurance in trained male kickboxers. β-Alanine is the rate-limiting precursor for skeletal muscle carnosine, an intramuscular buffer that can attenuate exercise-induced acidosis during repeated high-intensity efforts. Because kickboxing involves brief, repeated striking sequences with high glycolytic demand, BA may represent a practical, legal ergogenic aid for this population. Twenty-eight adult male kickboxers will be randomized (stratified) to BA (6.4 g·day-¹) or placebo for 4 weeks while maintaining habitual training and diet. Assessments will occur at baseline and post-intervention under standardized laboratory conditions and time-of-day control. The primary outcome is the total time on the Kickboxing Anaerobic Speed Test (KASTtotal; five consecutive sets of a validated four-technique striking combination with 10-s passive recovery). Secondary outcomes include best single-set time (KASTbest), individual set times (KAST₁-₅), Performance Decrement Index (PDI), countermovement jump (CMJ) and squat jump (SJ) height, and upper-body strength endurance (maximal push-ups and pull-ups performed to strict standards). Timing is determined from 25-fps video with frame-level analysis; jump height is derived via a validated smartphone application. Adverse events-particularly transient paresthesia-will be monitored throughout. The main analysis will use two-way repeated-measures ANOVA (group × time) with partial eta-squared to quantify effects; assumption checks and correction procedures will be applied as appropriate. BA will yield greater improvements than placebo in KASTtotal and upper-body strength endurance, with limited changes expected for jump performance.

Conditions

Anaerobic Performance; Athletic Performance Enhancement (Kickboxing); Strength Endurance; Neuromuscular Power; Nutritional Supplementation (β-Alanine)

Keywords

β-alanine; Kickboxing Anaerobic Speed Test; KAST; randomized double-blind placebo-controlled

Outcome Measures

Primary Outcomes (1)

• Total Time on Kickboxing Anaerobic Speed Test (KASTtotal)

  KASTtotal represents the cumulative time (in seconds) required to complete five consecutive sets of a standardized four-technique striking combination (jab-roundhouse-cross-roundhouse) performed at maximal intensity, with 10 seconds of passive recovery between sets. Timing begins at the first strike and ends at the completion of the final kick. This outcome reflects total anaerobic performance capacity under repeated high-intensity conditions specific to kickboxing.

  Baseline (Pre-supplementation) and after 4 weeks of supplementation (Post-intervention).

Secondary Outcomes (5)

• Best Single-Set Time (KASTbest)

  Baseline and Week 4

• Countermovement Jump Height (CMJ)

  Baseline and Week 4

• Squat Jump Height (SJ)

  Baseline and Week 4

• Push-up Repetitions

  Baseline and Week 4

• Pull-up Repetitions

  Baseline and Week 4

Study Arms (2)

β-Alanine Supplementation

EXPERIMENTAL

Participants receive 6.4 g of β-alanine per day for 4 weeks (e.g., 4 × 1.6 g divided doses). The supplement is provided as Hardline β-Alanine (Hardline Nutrition, Türkiye), standardized for active ingredient content.

Dietary Supplement: β-Alanine

Rice Flour

PLACEBO COMPARATOR

Participants receive a visually identical, flavor-matched placebo composed of rice flour, dosed equivalently to the experimental group (6.4 g·day-¹ for 4 weeks).

Dietary Supplement: Rice Flour (Placebo)

Interventions

β-Alanine DIETARY_SUPPLEMENT

Participants in the experimental group will receive 6.4 grams of β-alanine per day for 4 weeks, administered orally in four divided doses (1.6 g each). The supplement used is a commercially available β-alanine formulation (Hardline Nutrition, Türkiye), standardized for purity and active ingredient content. The dosing protocol follows established guidelines from prior ergogenic studies in athletes. Supplementation is supervised by the research team, and adherence is monitored weekly.

β-Alanine Supplementation

Rice Flour (Placebo) DIETARY_SUPPLEMENT

Participants in the placebo group will receive 6.4 grams of rice flour per day for 4 weeks, divided into four equal doses (1.6 g each) and identical in appearance, packaging, and flavor to the β-alanine supplement. The placebo is prepared and coded by an independent staff member to maintain double-blind conditions. All participants consume their assigned supplement orally each day under the same schedule, maintaining their normal training and diet routines.

Rice Flour

Eligibility Criteria

• Age: 18 Years - 35 Years
• Sex: male
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64)

You may qualify if:

• Healthy male kickboxers aged 18-35 years
• Minimum 5 years of systematic kickboxing training experience
• Actively engaged in competition or structured training within the last 12 months
• Free from any musculoskeletal injuries, metabolic, cardiovascular, or respiratory disorders that could affect high-intensity exercise performance
• Not currently taking any ergogenic aids, nutritional supplements, or medications known to influence performance or recovery
• Willing to maintain habitual diet and training routines throughout the study period
• Provided written informed consent before participation

You may not qualify if:

• Current or recent (\<6 months) musculoskeletal injury preventing maximal effort performance
• Metabolic, cardiovascular, or respiratory conditions that may increase risk during high-intensity activity
• Known allergy or intolerance to β-alanine
• Use of performance-enhancing supplements (e.g., creatine, caffeine, sodium bicarbonate, beta-alanine) in the past 4 weeks
• Any neurological, psychiatric, or endocrine disorder affecting physical performance or adherence
• Inability or unwillingness to comply with supplementation protocol or testing procedures

Sponsors & Collaborators

• Salih ÇABUK: lead

Study Sites (1)

Erzurum Technical University, Sport Laboratory

Erzurum, Yakutiye, Turkey (Türkiye)

Location

MeSH Terms

Interventions

Flour

Intervention Hierarchy (Ancestors)

Food; Diet, Food, and Nutrition; Physiological Phenomena; Food and Beverages

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: QUADRUPLE
• Who Masked: PARTICIPANT, CARE PROVIDER, INVESTIGATOR, OUTCOMES ASSESSOR
• Masking Details: Both participants and investigators are blinded to group allocation. Supplements are pre-packaged in identical, coded containers prepared by an independent staff member not involved in testing or data analysis. Coaches supervising the training sessions and all outcome assessors analyzing video and performance data are also blinded to the intervention codes until statistical analyses are complete.
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: SPONSOR INVESTIGATOR
• PI Title: Research Assistant

Model Details: Participants are randomized 1:1 (stratified by competitive level) to β-alanine or placebo in a parallel-group design. Allocation is concealed with blocked randomization; participants, investigators, coaches, and outcome assessors are blinded. No crossover or clustering; outcomes are assessed at baseline and after 4 weeks of supplementation.

Study Record Dates

• First Submitted: December 21, 2025
• First Posted: January 6, 2026
• Study Start: April 30, 2025
• Primary Completion: May 30, 2025
• Study Completion: June 4, 2025
• Last Updated: January 12, 2026

Record last verified: 2026-01

Locations

TU (1)