Phosphatidylserine, Taurine, and Caffeine for Cognitive Fatigue in Professional Football Players

NCT07696052 | Completed

• 1 other identifier: MIZERA -4-TCPS-FOOT-2026
• Study Type: interventional
• Target: 65
• Locations: 1 country
• Sites: 2

Brief Summary

This randomized, double-blind, placebo-controlled, parallel-group trial evaluated neurocognitive fatigue resistance and football-specific decision-making following 28 days of taurine-caffeine supplementation with or without phosphatidylserine in professional male football players. Sixty-five male outfield football players from two professional clubs were randomized to placebo, taurine plus caffeine, or taurine plus caffeine plus phosphatidylserine. Neurocognitive fatigue resistance was evaluated during a standardized high-load Stroop/Flanker task, while football-specific tactical decision-making, visual-search behavior, and field-based reactive decision performance were assessed at baseline and after 28 days of supplementation.

Conditions

Mental Fatigue; Cognitive Performance; Soccer Performance; Athletic Performance; Decision Making

Keywords

Phosphatidylserine; Taurine; Caffeine; Football Players; Soccer; Neurocognitive Load; Visual Search; Eye Tracking; Tactical Decision-Making; Stroop Flanker Task; Reactive Passing Decision Test; Sports Nutrition

Outcome Measures

Primary Outcomes (1)

• Tactical Inhibitory Decision Accuracy Under Neurocognitive Load

  Tactical inhibitory decision accuracy will be assessed using football-specific video clips requiring inhibition of an immediately attractive but suboptimal tactical action. Responses will be scored as 1 point for an optimal decision, 0.5 points for an acceptable decision, and 0 points for an incorrect decision. The outcome will be calculated as the mean score across inhibitory tactical clips. The score ranges from 0 to 1, with higher values indicating better tactical inhibitory decision accuracy.

  Baseline and 28 days of supplementation

Secondary Outcomes (10)

• Overall Football-Specific Optimal Decision Rate

  Baseline and 28 days of supplementation

• Football-Specific Decision Time

  Baseline and 28 days of supplementation

• Impulsive Tactical Error Rate

  Baseline and 28 days of supplementation

• Stroop/Flanker Time-on-Task Reaction-Time Trajectory

  Baseline and 28 days of supplementation

• Stroop/Flanker Reaction-Time Variability

  Baseline and 28 days of supplementation

Study Arms (3)

Placebo

PLACEBO COMPARATOR

Participants randomized to this arm will receive an inert placebo for 28 days. The placebo will be provided in identical coded packs matched for appearance, number of units, and packaging with the active supplements.

Dietary Supplement: Placebo

Taurine Plus Caffeine

ACTIVE COMPARATOR

Participants randomized to this arm will receive taurine 1500 mg/day plus caffeine 200 mg/day for 28 days. On training and testing days, the supplement will be consumed approximately 60 minutes before the main training session or testing procedure. On non-training days, it will be consumed at a consistent morning time.

Dietary Supplement: Taurine Plus Caffeine

Taurine, Caffeine, and Phosphatidylserine

EXPERIMENTAL

Participants randomized to this arm will receive taurine 1500 mg/day plus caffeine 200 mg/day plus phosphatidylserine 600 mg/day for 28 days. On training and testing days, the supplement will be consumed approximately 60 minutes before the main training session or testing procedure. On non-training days, it will be consumed at a consistent morning time.

Dietary Supplement: Taurine, Caffeine, and Phosphatidylserine

Interventions

Placebo DIETARY_SUPPLEMENT

Inert placebo matched with the active supplements for appearance, number of units, and packaging. The placebo will be administered for 28 days.

Placebo

Taurine Plus Caffeine DIETARY_SUPPLEMENT

Taurine 1500 mg/day plus caffeine 200 mg/day administered for 28 days. On training and testing days, the supplement will be consumed approximately 60 minutes before the main training session or testing procedure. On non-training days, it will be consumed at a consistent morning time.

Taurine Plus Caffeine

Taurine, Caffeine, and Phosphatidylserine DIETARY_SUPPLEMENT

Taurine 1500 mg/day plus caffeine 200 mg/day plus phosphatidylserine 600 mg/day administered for 28 days. On training and testing days, the supplement will be consumed approximately 60 minutes before the main training session or testing procedure. On non-training days, it will be consumed at a consistent morning time.

Taurine, Caffeine, and Phosphatidylserine

Eligibility Criteria

• Age: 18 Years - 37 Years
• Sex: male
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64)

You may qualify if:

• Male professional outfield football players aged 18 to 37 years.
• First-team players or selected U19 players aged 18 years or older who are regularly integrated into first-team training.
• Regular participation in club training.
• At least 5 years of systematic football training experience.
• Free from injury or illness limiting full participation in training and testing.
• Normal or corrected-to-normal vision.
• Ability to complete the laboratory and field-based testing procedures.
• Written informed consent provided before participation.

You may not qualify if:

• Goalkeepers.
• Current injury or illness limiting full participation in testing.
• Neurological disease.
• Recent concussion or head trauma.
• Uncorrected visual impairment.
• Use of phosphatidylserine, nootropic agents, or strong stimulants during the previous 4 weeks.
• Non-standard caffeine intake on testing days.
• Failure to comply with pre-test standardization procedures.
• Failed eye-tracker calibration.
• Loss of more than 30% of gaze data during the football-specific decision-making task.
• Withdrawal of consent.

Sponsors & Collaborators

• Vizja University in Warsaw: lead
• Józef Piłsudski University of Physical Education: collaborator

Study Sites (2)

Professional Football Training Center

Lodz, Poland

Location

Professional Football Training Center

Warsaw, Poland

Location

MeSH Terms

Conditions

Mental Fatigue

Interventions

Taurine; Caffeine; Phosphatidylserines

Condition Hierarchy (Ancestors)

Fatigue; Signs and Symptoms; Pathological Conditions, Signs and Symptoms; Behavioral Symptoms; Behavior

Intervention Hierarchy (Ancestors)

Alkanesulfonic Acids; Alkanes; Hydrocarbons, Acyclic; Hydrocarbons; Organic Chemicals; Sulfonic Acids; Sulfur Acids; Sulfur Compounds; Xanthines; Alkaloids; Heterocyclic Compounds; Purinones; Purines; Heterocyclic Compounds, 2-Ring; Heterocyclic Compounds, Fused-Ring; Glycerophospholipids; Phosphatidic Acids; Glycerophosphates; Phospholipids; Membrane Lipids; Lipids

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: QUADRUPLE
• Who Masked: PARTICIPANT, CARE PROVIDER, INVESTIGATOR, OUTCOMES ASSESSOR
• Masking Details: Participants, investigators, relevant club staff involved in supplementation, and outcome assessors were blinded to treatment allocation. Study products were provided in identically coded packages matched for appearance, number of units, and total mass. The allocation sequence was retained by an independent individual not involved in recruitment, supplementation, outcome assessment, data management, or statistical analysis. Treatment codes were not released until completion of the prespecified primary analysis.
• Purpose: OTHER
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Principal Investigator and Assistant Professor

Model Details: Participants were randomized in a 1:1:1 ratio to one of three parallel groups: placebo, taurine plus caffeine, or taurine plus caffeine plus phosphatidylserine. The intervention lasted 28 days, and outcomes were assessed at baseline and after the supplementation period.

Study Record Dates

• First Submitted: July 5, 2026
• First Posted: July 10, 2026
• Study Start: August 6, 2026
• Primary Completion: September 8, 2026
• Study Completion: September 8, 2026
• Last Updated: September 14, 2026

Record last verified: 2026-09

Data Sharing

• IPD Sharing: Will not share

Locations

PL (2)