Not Yet RecruitingNot Applicable

Placebo Effect in Field-Based Physical Performance

Poland120 participantsStarted 2026-09-01

Plain-language summary

This study aims to investigate the placebo (PLA) effect on physical performance across different sports disciplines in real-world, field-based settings. The study investigates how participant expectations and beliefs regarding caffeine (CAF) intake influence physical performance and psychomotor function outside the controlled laboratory environment. Healthy, physically active adults (n = 120) from diverse sports backgrounds will be randomly assigned to receive caffeine, placebo, or no intervention. Participants will perform discipline-specific field exercise tests (e.g., running-based protocols or repeated sprint protocols) while physiological responses are monitored using wearable technology. Physical performance outcomes and psychomotor responses will be analyzed to evaluate the real-world impact of the placebo effect and to distinguish the pharmacological effects of caffeine from those driven by psychological expectations across different athletic settings.

Who can participate

Age range

20 Years – 35 Years

Sex

ALL

See this in plain English?

AI-rewrites the medical criteria so a patient or caregiver can understand them. Always confirm with the trial site.

Inclusion Criteria: * Age between 20 and 35 years, * Healthy adults, * Regular physical activity, * Normal or corrected-to-normal vision, * Habitual caffeine consumption. Exclusion Criteria: * History of neurological, psychiatric, cardiovascular, or metabolic disorders, * Current use of medication or supplements affecting the central nervous system, * Musculoskeletal injuries that would impair physical performance, * No habitual caffeine consumption or severe negative side effects of caffeine, * Diagnosed sleep disorders or chronic fatigue, * Diagnosed major depressive disorder or other severe psychiatric conditions, * Presence of any menstrual disorders, * Inability to attend all experimental study visits.

Questions worth asking your doctor

Bring these to your next appointment. They're a starting point for a shared conversation — not a sign you qualify or a recommendation to enrol.

1Based on my diagnosis and history, is this trial worth exploring for me — or is there a standard treatment we should try first?
2What does this trial's phase tell us about how much is already known about its safety and benefit?
3What would taking part actually involve for me — visits, tests, time, and travel?
4What are the known and possible risks or side effects I should weigh, and how would they be monitored?
5If this trial isn't the right fit, what other options or trials would you suggest I look into?

Generated to help you prepare — always confirm anything about your own eligibility and care with the study team and your doctor.

Questions for the trial coordinator

The trial coordinator is the person who runs the study day to day. These cover the practical side — logistics, costs, and what taking part would actually mean for your life. The study team confirms whether you meet the criteria; these are questions to ask, not a sign you qualify.

1What does taking part actually involve week to week — how many visits, where, and how long does each one take?
2What costs are covered by the study, and what might I have to pay for myself, including travel, parking, or time off work?
3What happens during screening, and what happens if the study team confirms I don't meet the criteria after those tests?
4Who pays for the scans, blood work, and other tests the trial requires — the study, my insurance, or me?
5How will being in the trial affect my regular care, and will my own doctor stay informed and involved?
6Can I leave the trial at any point if I change my mind, and what would happen to my care if I do?

A starting point for the conversation — always confirm anything about your own eligibility, costs, and care with the study team and your doctor.

What they're measuring

Physical Performance Capacity (total distance in running, metres)

Timeframe: Measured during the exercise protocol immediately following administration of the study intervention.

Physical Performance Capacity (total work in Joules for cycling)

Timeframe: Measured during the exercise protocol immediately following administration of the study intervention.

Physical Performance Capacity (exercise duration until exhaustion, minutes)

Timeframe: Measured during the exercise protocol immediately following administration of the study intervention.

Trial details

NCT IDNCT07742150

SponsorPoznan University of Physical Education

Sponsor typeOTHER

Study typeINTERVENTIONAL

Primary completion2028-03-31

Contact for this trial

Jakub Malik, PhD

+48739975701 malik@awf.poznan.pl

View on ClinicalTrials.gov More Physical Performance trials

Plain-language summary

Who can participate

Age range

20 Years – 35 Years

Sex

ALL

See this in plain English?

AI-rewrites the medical criteria so a patient or caregiver can understand them. Always confirm with the trial site.

What they're measuring

Physical Performance Capacity (total distance in running, metres)

Timeframe: Measured during the exercise protocol immediately following administration of the study intervention.

Physical Performance Capacity (total work in Joules for cycling)

Timeframe: Measured during the exercise protocol immediately following administration of the study intervention.

Physical Performance Capacity (exercise duration until exhaustion, minutes)

Timeframe: Measured during the exercise protocol immediately following administration of the study intervention.