Caffeine Supplementation and Strength Endurance in Brazilian Jiu-jitsu Athletes (CAF-BJJ)

Federal University of Minas Gerais

Status: Completed

Conditions: Muscle Strength; Physical Endurance; Exercise

Treatments: Other: Placebo; Dietary Supplement: Caffeine

Study type: Interventional

Funder types: Other

Identifiers

NCT07479875

8.062.851

Details and patient eligibility

About

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.

Full description

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.

Enrollment: 15 patients

Sex: Male

Ages: 18 to 35 years old

Volunteers: Accepts Healthy Volunteers

Inclusion criteria

• 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

Exclusion criteria

• 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

Trial design

Primary purpose: Basic Science

Allocation: Randomized

Interventional model: Crossover Assignment

Masking: Triple Blind

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15 participants in 2 patient groups, including a placebo group

Placebo

Placebo Comparator group

Description:

Capsule containing 400 mg of starch (placebo), ingested 30 minutes before testing.

Treatment:

Other: Placebo

Caffeine

Experimental group

Description:

Capsule containing 400 mg of anhydrous caffeine, ingested 30 minutes before testing.

Treatment:

Dietary Supplement: Caffeine