Effects of L-Tyrosine and Caffeine Supplementation on Cognitive, Physical, and Physiological Parameters in Elite Boxers: A Randomized Double-Blind Placebo-Controlled Crossover Study
试验速览
- 阶段
- 不适用
- 状态
- 尚未招募
- 入组人数
- 18
- 试验地点
- 1
- 主要终点
- Stroop Test Performance
研究概览
简要总结
Participants will complete six sessions, including one familiarization and baseline session followed by five experimental conditions: control (no supplementation), placebo, L-tyrosine, caffeine, and combined L-tyrosine plus caffeine. The experimental conditions will be performed in a randomized, counterbalanced crossover design with a washout period of at least 72 hours between sessions. Resting physiological and cognitive assessments will be performed during the familiarization session, while biochemical, cognitive, and boxing-specific performance assessments will be conducted before and after each experimental session.
详细描述
Participants will attend six sessions in total. The first session will be used for familiarization and baseline assessments, including anthropometric measurements, resting physiological measurements, and cognitive performance testing. The remaining five sessions will consist of one control condition (no supplementation) and four randomized experimental conditions (placebo, L-tyrosine, caffeine, and combined L-tyrosine plus caffeine) administered in a randomized, counterbalanced crossover design.
Each experimental session will be separated by a washout period of at least 72 hours. During the placebo, L-tyrosine, caffeine, and combined supplementation conditions, the assigned intervention will be administered 60 minutes before exercise. No supplement will be administered during the control condition.
Before and immediately after each experimental session, venous blood samples will be collected to assess brain-derived neurotrophic factor (BDNF) and oxidative stress biomarkers, including total antioxidant status (TAS), total oxidant status (TOS), malondialdehyde (MDA), superoxide dismutase (SOD), and glutathione peroxidase (GPx). Cognitive performance will be evaluated using the computerized Stroop test, and boxing-specific physical performance will be assessed using a standardized boxing simulation protocol. Heart rate and rating of perceived exertion (RPE) will also be recorded during the exercise protocol.
研究设计
- 研究类型
- Interventional
- 分配方式
- Randomized
- 干预模型
- Crossover
- 主要目的
- Basic Science
- 盲法
- Double (Participant, Investigator)
盲法说明
Both participants and investigators are blinded to the supplementation conditions. Supplements are prepared and coded by an independent researcher to ensure double-blind conditions.
入排标准
- 年龄范围
- 18 Years 至 —（Adult, Older Adult）
- 性别
- Male
- 接受健康志愿者
- 是
入选标准
- •Male elite boxers aged ≥18 years At least 8 years of boxing training experience Active participation in national or international competitions Regular training schedule No injury or illness affecting performance
排除标准
- •Use of nutritional supplements or stimulants within the last 4 weeks Any cardiovascular, metabolic, or neurological disorder Current injury or musculoskeletal limitation Smoking or excessive caffeine intake Failure to comply with study procedures
研究组 & 干预措施
Placebo
Participants receive placebo condition.
干预措施: Placebo (Dietary Supplement)
Combined
Participants receive combined supplementation condition.
干预措施: L-tyrosine + Caffeine (Dietary Supplement)
Caffeine
Participants receive caffeine condition.
干预措施: Caffeine (Dietary Supplement)
L-tyrosine
Participants receive L-tyrosine condition.
干预措施: L-Tyrosine (Dietary Supplement)
Control
Participants complete the experimental protocol without receiving placebo or active supplementation. Baseline cognitive, physiological, and physical performance assessments are performed under the control condition.
结局指标
主要结局
Stroop Test Performance
时间窗: up to 12 weeks
Cognitive performance assessed using the Stroop test, including reaction time and accuracy.
次要结局
- BDNF Levels(up to 12 weeks)
- Oxidative Stress Markers(up to 12 weeks)
研究者
Halil UÇAR
Research Assistant and PhD Student
Inonu University