Effects of Supplementation on Performance in Football Players

This randomized, placebo-controlled, single-blind study evaluated the effects of combined supplementation with taurine, caffeine, and phosphatidylserine on physical and cognitive performance in professional male football players.

Eighty-one participants aged 19-32 years were randomly assigned to one of three groups: placebo (lactose), taurine plus caffeine (1500 mg taurine + 200 mg caffeine), or taurine plus caffeine plus phosphatidylserine (1500 mg taurine + 150 mg caffeine + 300 mg phosphatidylserine daily for 10 days). All participants completed a 10-day supplementation period, followed by a standardized 105-minute football training session.

Outcome measures included sprint performance (30 m sprint time), reaction time (visual and auditory), GPS-derived variables (total distance, sprint activity, speed, accelerations, and decelerations), and technical and tactical performance indicators assessed by coaching staff and video analysis.

The study was conducted under controlled environmental conditions and in accordance with standardized training procedures. Data were analyzed using analysis of variance (ANOVA) with post hoc testing. The aim was to determine whether multi-ingredient supplementation could enhance performance and reduce fatigue-related declines in a football-specific setting.

• Placebo (Other): Placebo (lactose) administered daily for 10 days
• Taurine and Caffeine (Dietary supplement): Taurine 1500 mg and caffeine 200 mg administered daily for 10 days
• Taurine, Caffeine, and Phosphatidylserine (Dietary supplement): Taurine 1500 mg, caffeine 150 mg, and phosphatidylserine 300 mg administered daily for 10 days

Primary outcomes

• 30 m sprint time (seconds) [Day 10 (final training session following supplementation)]: Time to complete a 30 meter sprint under standardized conditions, expressed in seconds; calculated as the mean of valid trials.

Secondary outcomes

• Reaction time (visual and auditory) [Day 10 (post-supplementation)]: Visual and auditory reaction time measured using standardized computerized reaction time tests (e.g., validated software-based assessment tools), expressed as mean response time in seconds across valid trials.
• Total distance (meters) [Day 10 (during standardized training session)]: Total distance covered during the standardized training session, measured using GPS tracking devices (e.g., 10 Hz GPS units), expressed in meters.
• Running speed (m/s) [Day 10 (during standardized training session)]: Mean running speed during the standardized training session, measured using GPS tracking devices (e.g., 10 Hz GPS units), expressed in meters per second.
• Sprint count (number) [Day 10 (during standardized training session)]: Total number of sprint efforts recorded during the standardized training session using GPS tracking devices.
• High-speed running distance (meters) [Day 10 (during standardized training session)]: Distance covered at high-speed running thresholds during the standardized training session, measured using GPS tracking and expressed in meters.

Other outcomes

• Sprint time decline (%) [Day 10 (during final training session; comparison between first and second halves)]: Percentage decline in 30 m sprint time between the first and second halves of the standardized training session, measured using electronic timing gates and expressed as percentage change.
• Running speed decline (%) [Day 10 (during final training session; comparison between first and second halves)]: Percentage decline in running speed between the first and second halves of the standardized training session, measured using GPS tracking devices and expressed as percentage change.
• Passing accuracy (%) [Day 10 (during standardized training session)]: Percentage of successful passes during the standardized training session, assessed using video-based performance analysis and expressed as a percentage.
• Dribbling success (%) [Day 10 (during standardized training session)]: Percentage of successful dribbling attempts during the standardized training session, assessed using video-based performance analysis and expressed as a percentage.
• Ball recoveries (number) [Day 10 (during standardized training session)]: Total number of ball recoveries performed during the standardized training session, assessed using video-based performance analysis and expressed as a count.
• Tactical performance score (units) [Day 10 (during standardized training session)]: Coach-rated tactical performance during the standardized training session, including positioning, decision-making, and support play, assessed using a standardized rating scale and expressed in standardized score units.

Sex: Male, ages: 19 Years to 32 Years, accepts healthy volunteers

Inclusion Criteria:

* Male professional football (soccer) players
* Age 19-32 years
* Currently participating in regular team training (4-5 sessions per week)
* Medically cleared for participation in high-intensity physical activity
* Provided written informed consent

Exclusion Criteria:

* Current injury or musculoskeletal condition affecting performance
* Chronic disease or medical condition
* Use of medications that may affect physical or cognitive performance
* Regular use of dietary supplements or caffeine prior to the study period
* Smoking or alcohol consumption
* Failure to comply with study procedures

• Krzysztof Maciej MIZERA, PhD, Principal investigator, 1. Vizja University in Warsaw, Faculty of Medical Sciences and Health Sciences, 01-143 Warsaw, Poland