Effects of Six Weeks of Beta-Alanine Supplementation on Exercise Performance and Fatigue-Related Outcomes in Competitive Adolescent Female Karate Athletes: A Randomized, Double-Blind, Placebo-Controlled Trial

This study examined whether six weeks of beta-alanine supplementation improves physical performance and fatigue-related outcomes in competitive adolescent female karate athletes.

A randomized, double-blind, placebo-controlled clinical trial with parallel groups was conducted in 24 adolescent female karate athletes aged 15–18 years. Participants were allocated to two parallel groups of 12: (1) an intervention group receiving beta-alanine (3.2 g/day) for six weeks, and (2) a control group receiving a placebo for six weeks. Random allocation was performed using a computer-generated random-number sequence by an individual who was not involved in outcome assessment.

The study was conducted at karate clubs in Mahabad. The study was conducted using a double-blind design. The beta-alanine and placebo capsules were matched in size, color, weight, appearance, and packaging. An independent individual handled the distribution and coding of the supplements. Participants and outcome assessors remained unaware of group allocation until the final assessments.

Eligible participants were female karate athletes aged 15–18 years who had at least three years of continuous karate training, held a brown belt (Dan 1) or higher, and had participated in at least one provincial-level or higher competition during the previous year. Additional inclusion criteria were absence of acute or chronic cardiovascular, metabolic, renal, or hepatic disease;

The beta-alanine supplementation group and the control group, which receives a placebo.

400-m running time; Standing broad-jump distance; Multidimensional fatigue (MFI); Rating of perceived exertion (RPE); Post-exercise muscle soreness; Simple visual reaction time

After eligibility screening and baseline assessment, participants were randomly allocated to the beta-alanine or placebo group using a computer-generated random-number sequence. Allocation was performed by an independent individual who was not involved in subsequent outcome assessments.

To ensure a double-blind design and minimize bias, the beta-alanine supplement and placebo (maltodextrin) were prepared in capsules identical in appearance, size, color, texture, weight, and smell. Both supplements were packaged in identical, opaque containers. Coding and labeling of the containers (e.g., as ‘Code A’ and ‘Code B’) were conducted by an independent researcher who was not involved in participant recruitment, training supervision, or outcome assessments. Consequently, both the participants and the evaluators conducting the physical performance tests remained blind to group allocations throughout the intervention and data collection. The allocation code was concealed in a sealed envelope and remained undisclosed until all statistical analyses were completed

The data have been coded, and the participants cannot be identified. The information will be reported anonymously in the thesis and in any article published later.

from 2027

researcher

Only the researchers and the editor of the journal in which we intend to publish the article in the future will have access to the data.

Supervisor: Mohammad Azizi, faculty member at Razi University. azizimihammad@gmail.com

The request and the reason for requesting the data will be reviewed, and the data will then be emailed as soon as possible (within 48 hours).