Caffeine Supplementation and Strength Endurance in Brazilian Jiu-jitsu Athletes
试验速览
- 阶段
- 不适用
- 状态
- 已完成
- 发起方
- 入组人数
- 15
- 试验地点
- 1
- 主要终点
- Dynamic component of the Kimono Grip Strength Test (Maximum Number of Repetitions, MNR)
研究概览
简要总结
This study investigated the acute effects of ingesting 400 mg of caffeine administered 30 minutes before Brazilian jiu-jitsu-specific strength endurance tests. Experienced athletes completed two conditions, placebo and caffeine, in a randomized, double-blind, crossover clinical trial. Performance was assessed using the dynamic component of the kimono grip strength test (maximum number of repetitions, MNR) and the isometric component (maximum static lift, MSL), both performed with a gi grip. Rating of perceived exertion, adverse effects, and blinding effectiveness were also evaluated.
详细描述
Caffeine is a widely used ergogenic aid in combat sports due to its effects on alertness, strength, and muscular endurance. This study evaluated whether an absolute dose of 400 mg of caffeine, ingested 30 minutes before testing, improved performance in Brazilian jiu-jitsu-specific strength endurance tests performed with a gi grip.
Fifteen experienced athletes completed two experimental sessions separated by at least seven days in a randomized, double-blind, crossover design. In each session, participants performed three maximal sets of the dynamic component of the kimono grip strength test (maximum number of repetitions, MNR) and three trials of the isometric component (maximum static lift, MSL). Dietary intake was controlled during the 24 hours preceding each session, and athletes were instructed to avoid stimulant substances.
Adverse effects were monitored for 24 hours following each session, and blinding effectiveness was assessed using the Bang blinding index. The study also examined interindividual variability in response to caffeine supplementation.
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
- Triple (Participant, Investigator, Outcomes Assessor)
盲法说明
Caffeine and placebo capsules were identical in color, size, shape, and taste. Randomization was performed by a researcher not involved in data collection. Neither the participants nor the assessors were aware of which substance was administered in each session. The allocation code was revealed only after the completion of the data analysis.
入排标准
- 年龄范围
- 18 Years 至 35 Years（Adult）
- 性别
- Male
- 接受健康志愿者
- 是
入选标准
- •Adult men
- •Brazilian Jiu-Jitsu athletes
- •Minimum of 5 years of continuous practice
- •Participation in competitions within the past 12 months
- •Absence of upper-limb injuries
- •No use of caffeine or stimulant substances within 48 hours prior to testing
- •Availability to attend both experimental sessions
- •Physical fitness to perform maximal strength tests
排除标准
- •Recent musculoskeletal injuries
- •Use of stimulant substances, pre-workout supplements, or thermogenic products
- •Known hypersensitivity to caffeine
- •Clinical conditions that could limit participation (cardiovascular, respiratory, or neurological)
- •Failure to attend any experimental session
- •Noncompliance with pre-test nutritional guidelines
研究组 & 干预措施
Caffeine
Capsule containing 400 mg of anhydrous caffeine, ingested 30 minutes before testing.
干预措施: Caffeine (Dietary Supplement)
Placebo
Capsule containing 400 mg of starch (placebo), ingested 30 minutes before testing.
干预措施: Placebo (Other)
结局指标
主要结局
Dynamic component of the Kimono Grip Strength Test (Maximum Number of Repetitions, MNR)
时间窗: During each experimental session, following intervention administration (two sessions, approximately 7 days apart).
Brazilian jiu-jitsu-specific strength endurance test performed using a kimono grip on a pull-up bar. Participants completed three maximal sets of the dynamic component of the Kimono Grip Strength Test (maximum number of repetitions, MNR), and the total number of valid repetitions was recorded.
Isometric component of the Kimono Grip Strength Test (Maximum Static Lift, MSL)
时间窗: During each experimental session, following intervention administration (two sessions, approximately 7 days apart).
Maximum isometric holding time (seconds) during the isometric component of the Kimono Grip Strength Test. Participants maintained an isometric position at approximately 90 degrees of elbow flexion using a kimono grip on a pull-up bar, and the maximal hold time was recorded.
次要结局
- Interindividual Response Variability(At study completion, after the second experimental session (two sessions approximately 7 days apart).)
- Rating of perceived exertion (Borg CR10 scale)(During each experimental session, at the end of testing following intervention administration (two sessions, approximately 7 days apart).)
- Bang blinding index(At the end of each experimental visit following intervention administration (two visits, approximately 7 days apart).)
- Acute Adverse Effects(Within 24 hours after each experimental session following intervention administration (two sessions, approximately 7 days apart).)
研究者
FRANCISCO DE PAULA VITOR FERREIRA
Principal Investigator
Federal University of Minas Gerais