Beta Alanine Supplementation, Placebo - Control
Conditions
Keywords
dietary supplements, team sports, female
Brief summary
This study will examine the effects of beta-alanine supplementation on physical performance in female rugby players, who will ingest 4.8 grams/day over a four-week period. The research will evaluate both cardiovascular and neuromuscular outcomes, with cardiovascular performance assessed using the Bronco Test (a field-based measure of endurance and repeated high-intensity running ability) and neuromuscular performance (e.g.vertical jump capacity).
Detailed description
This study will examine the effects of beta-alanine supplementation on physical performance in female rugby players, who will ingest 4.8 grams/day over a four-week period. Beta-alanine is a dietary supplement known to increase muscle carnosine levels, which may enhance buffering capacity and delay fatigue during high-intensity exercise. The research will evaluate both cardiovascular and neuromuscular outcomes, providing a comprehensive assessment of performance adaptations relevant to rugby. Cardiovascular performance will be assessed using the Bronco Test, a validated field-based measure of endurance and the ability to perform repeated high-intensity running efforts. Neuromuscular performance will be evaluated through measures of upper and lower-body strength /power output. Additionally, the study aims to explore whether beta-alanine supplementation can improve the ability to sustain high-intensity actions and overall physical readiness in female team-sport athletes.
Interventions
DIETARY_SUPPLEMENTPlacebo Comparator
Placebo group will receive 4.8 grams per day of placebo, containing fructose (3000 mg) and excipients (1800 mg) such as cellulose, calcium phosphate, silicon dioxide, and magnesium stearate. Both supplements will be matched in appearance and dosing schedule to ensure proper blinding. Compliance with the supplementation protocol will be monitored throughout the intervention period.
DIETARY_SUPPLEMENTBeta-Alanine
Participants assigned to the experimental group will receive beta-alanine supplementation (CROWN Sport Nutrition, La Rioja, España) at a dose of 4.8 grams per day for a period of four weeks . The supplement will be administered in divided doses throughout the day to enhance absorption and minimize potential side effects such as paresthesia
Sponsors
Universidad Pontificia Comillas
University of Seville
Universidad Complutense de Madrid
Universidad Francisco de Vitoria
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
TRIPLE (Subject, Caregiver, Investigator)
Masking description
An independent researcher who will not be involved in the implementation of the study, data collection, or analysis will be responsible for the allocation concealment and preparation of the supplementation (beta-alanine and placebo). This individual will ensure proper blinding of the interventions so that participants and study personnel involved in outcome assessment remain unaware of group assignments.
Intervention model description
This study will use a randomized, parallel-group design. Participants will be randomly assigned to one of two groups: an experimental group receiving beta-alanine supplementation (4.8 g/day) or a control group receiving a placebo. Both groups will follow the same supplementation protocol over a four-week period. This design will allow for the comparison of the effects of beta-alanine versus placebo on cardiovascular and neuromuscular performance outcomes in female rugby players.
Eligibility
Sex/Gender
FEMALE
Age
18 Years to 40 Years
Healthy volunteers
Yes
Inclusion criteria
* Rugby participants with at least three years of professional experience.
Exclusion criteria
* Suffering from any chronic pathology or an injury in the month prior to the investigation. * Intolerance to beta-alanine supplementation * Participants aged outside the range of 18 to 40 years.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Bronco Test (Cardiovascular Test) | Before and after the intervention period, which lasted four weeks. | The Bronco Test will be used to assess cardiovascular fitness and the ability to perform repeated high-intensity running efforts. This field-based test consists of continuous shuttle running over increasing distances (typically 20, 40, and 60 meters) repeated multiple times without rest, totaling 1,200 meters. Participants are required to complete the test as quickly as possible, with total time recorded as the main performance outcome. The Bronco Test is widely used in team sports such as rugby due to its strong ecological validity, as it reflects the intermittent and high-intensity nature of match play. Improvements in completion time are indicative of enhanced aerobic capacity, speed endurance, and overall cardiovascular performance. |
| Repeated sprint ability capacity | Before and after the intervention period, which lasted four weeks. | Repeated-sprint ability will be assesed using a 6 × 30 m repeated-sprint test, from which two indices were derived: total sprint time and percent sprint decrement. Total sprint time was calculated as the sum of the six individual sprint times, expressed in seconds, and represents overall sprint performance across repeated efforts. The percent sprint decrement was used as an indicator of fatigue, reflecting the decline in performance across successive sprints. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Isometric handgrip strength | Before and after the intervention period, which lasted four weeks. | Isometric handgrip strength will be assessed using a calibrated handgrip dynamometer. Participants will perform the test in a standardized position (standing), with the arm fully extended elbow and without contact with the body. After a brief familiarization, participants will be instructed to squeeze the dynamometer with maximal effort for 3-5 seconds. Two trials will be performed for each hand, with adequate rest between attempts to avoid fatigue. The highest value recorded (Newtons) will be used for analysis. |
| Vertical jump capacity (countermovement jump) | Before and after the intervention period, which lasted four weeks. | Vertical jump performance will be assessed using the countermovement jump (CMJ) test, a widely used measure of lower-body neuromuscular performance. Participants will begin in an upright standing position, then perform a rapid downward movement (eccentric phase) followed immediately by a maximal upward jump (concentric phase), with hands placed on the hips to eliminate arm swing. Jump height will be recorded using a validated measurement system (contact mat). Participants will perform two maximal attempts and the best performance will be used for analysis. |
| Modified agility T-test | Before and after the intervention period, which lasted four weeks. | Agility will be assessed using the Modified Agility T-test measure by photocells, a reliable and sport-specific measure of change-of-direction speed. Participants will start behind the starting line, sprint forward to a central cone, shuffle laterally to one side, then move across to the opposite side, and finally return to the center before backpedaling to the starting position. The modified version typically involves shorter distances and emphasizes lateral movements relevant to team sports such as rugby. Performance time will be recorded using electronic timing gates. or a stopwatch, with faster times indicating better agility performance. Participants will perform two trials with adequate rest between attempts, and the best time will be used for analysis. This test evaluates multidirectional speed, coordination, and the ability to rapidly change direction, all of which are essential components of rugby performance. |
| Rate of perceived exertion (RPE) | Before and after the intervention period, which lasted four weeks. | Rate of perceived exertion will be assessed using the Borg 6-20 scale to quantify participants' subjective perception of effort during exercise. Participants will be asked to rate their level of exertion immediately after training session by selecting a number that best reflects how hard the effort felt, ranging from 6 (no exertion at all) to 20 (maximal exertion). The Borg 6-20 scale is a valid and reliable tool that correlates well with physiological markers such as heart rate, and it is widely used to monitor internal load and exercise intensity in both research and applied sport settings. |
Countries
Spain
Outcome results
None listed