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The Influence of Caffeine Supplementation on Specific Performance and Training Activities

Phase 3
Completed
Conditions
Supplementation
Sports
Registration Number
NCT03822663
Lead Sponsor
Poznan University of Physical Education
Brief Summary

The purpose of this study is to verify the effect of acute caffeine (CAF) and placebo (PLA) supplementation on physical capacity and discipline-specific exercise performance in athletes, in a randomised, double-blind, placebo-controlled crossover trial.

Detailed Description

Caffeine (CAF) is often proposed as an ergogenic agent, especially during high-intensity efforts. CAF supplementation may reduce effort-induced multi-faceted symptoms of fatigue and can improve psychomotor functions (like agility or decision-making processes), which is required during the intermittent high-intensity efforts in combat sports and speed-strength disciplines. Moreover, it is suggested that CAF treatment is associated with increased glycolytic activity during simulated or real training/competition bouts, which results in performance and physical capacity improvement.

However, there are hardly any data on the individual CAF-induced and dose-dependent changes in physical capacity and discipline-specific performance in combat sports and speed-strength disciplines. Therefore, the study aims to examine the effect of acute, different-dose CAF ingestion on physical capacity and discipline-specific performance in combat sports and speed-strength athletes, in a randomized, double-blind, placebo-controlled crossover trial.

Recruitment & Eligibility

Status
COMPLETED
Sex
All
Target Recruitment
26
Inclusion Criteria
  • written consent to participate,
  • a current medical clearance to practice sports,
  • training experience: at least 2 years,
  • minimum of 4 workout sessions (in the discipline covered by the study) a week.
Exclusion Criteria
  • current injury,
  • any health-related contraindication,
  • declared general feeling of being unwell,
  • unwilling to follow the study protocol.

Study & Design

Study Type
INTERVENTIONAL
Study Design
CROSSOVER
Primary Outcome Measures
NameTimeMethod
Changes in discipline-specific exercise capacity after caffeine supplementation and placebo treatmentBaseline and during 1 day of acute CAF and PLA supplementation

Assessment of the discipline-specific exercise capacity tests carried out at baseline, and after CAF and PLA supplementation

Changes in reaction and motor time (Vienna Test System) after caffeine supplementation and placebo treatmentBaseline and during 1 day of acute CAF and PLA supplementation

Assessment of the reaction and motor time (Vienna Test System) (ms) before and after discipline-specific exercise tests carried out at baseline, and after CAF and PLA supplementation

Changes in postural stability indices (area 95 percentile, Area95) (posturographic platform AccuGaitTM) after caffeine supplementation and placebo treatmentBaseline and during 1 day of acute CAF and PLA supplementation

Assessment of the postural stability indices (area 95 percentile, Area95) (posturographic platform AccuGaitTM) (cm2) before and after discipline-specific exercise tests carried out at baseline, and after CAF and PLA supplementation

Changes in postural stability indices (COP velocity, Vcop) (posturographic platform AccuGaitTM) (after caffeine supplementation and placebo treatmentBaseline and during 1 day of acute CAF and PLA supplementation

Assessment of the postural stability indices (COP velocity, Vcop) (posturographic platform AccuGaitTM) (cm/s) before and after discipline-specific exercise tests carried out at baseline, and after CAF and PLA supplementation

Changes in caffeine and paraxanthine concencentrations in serum and saliva before and after caffeine supplementation and placebo treatmentBaseline and during 1 day of acute CAF and PLA supplementation

Assessment of the caffeine and paraxanthine concencentrations (μg/mL), and paraxanthine/caffeine ratio in serum and saliva before and after discipline-specific exercise tests carried out at baseline, and after CAF and PLA supplementation. Additionally CYP1A2 enzyme activity was assessed by the determination of the mean time-corrected PRX/CAF RATIO in saliva.

Secondary Outcome Measures
NameTimeMethod
Changes in lactate and pyruvate concentrations in capillary blood before and after caffeine supplementation and placebo treatmentBaseline and during 1 day of acute CAF and PLA supplementation

Assessment of the lactate and pyruvate concentration (mmol/L) in capillary blood before and after discipline-specific exercise tests carried out at baseline, and after CAF and PLA supplementation

Analysis of gene polymorphismsBaseline

Assessment of the chosen gene polymorphisms in saliva carried out at baseline

Changes in sports training / competition activities after discipline-specific exercise testsBaseline and during 1 day of acute CAF and PLA supplementation

Assessment of the sports training / competition activities after discipline-specific exercise tests carried out at baseline, and after CAF and PLA supplementation

Changes in heart rate during discipline-specific exercise testsBaseline and during 1 day of acute CAF and PLA supplementation

Assessment of the Heart Rate during and after discipline-specific exercise tests carried out at baseline, and after CAF and PLA supplementation

Analysis of psychological state before and after caffeine supplementation and placeboBaseline and during 1 day of acute CAF and PLA supplementation

Assessment of psychological state by chosen questionnaires was carried out before and after discipline-specific exercise tests carried out at baseline, and after CAF and PLA supplementation

Analysis of macronutrients in diets before and after caffeine supplementation and placebo treatmentBaseline and during 1 day of acute CAF and PLA supplementation

Assessment of the macronutrients in diets (g) was carried out before the execution of exercise protocols on each research visit

Analysis of body composition (fat-free mass, fat mass)Baseline and during 1 day of acute CAF and PLA supplementation

Assessment of body composition (fat-free mass, fat mass) (kg) was carried out before the execution of exercise protocols on each research visit

Analysis of body composition (total body water)Baseline and during 1 day of acute CAF and PLA supplementation

Assessment of body composition (total body water) (%) was carried out before the execution of exercise protocols on each research visit

Changes in rate of perceived exertion after discipline-specific exercise testsBaseline and during 1 day of acute CAF and PLA supplementation

Assessment of the Borg Rating of Perceived Exertion (RPE) scale after discipline-specific exercise tests carried out at baseline, and after CAF and PLA supplementation

Trial Locations

Locations (1)

Department of Sports Dietetics, Poznan University of Physical Education

🇵🇱

Poznań, Wielkopolska, Poland

Department of Sports Dietetics, Poznan University of Physical Education
🇵🇱Poznań, Wielkopolska, Poland

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