Placebo Effect on Cycling Performance: Laboratory Crossover Study
15 settembre 2026 aggiornato da: Poznan University of Physical Education
The Impact of Expectations on Physical Performance and Psychophysiological Potential: a Randomized, Double-blind, Placebo-controlled Crossover Study on the Placebo Effect in the Context of Caffeine Supplementation
This study aims to determine the impact of the placebo (PLA) effect on physical and cognitive performance in a controlled laboratory setting.
The study investigates how expectations and beliefs about substance intake (caffeine vs. placebo) interact with actual consumption to influence performance and physiological stress markers.
Healthy adults (n = 80) will participate in four testing sessions using a randomized, double-blind, placebo-controlled crossover design.
Physiological stress markers (cortisol and alpha-amylase), heart rate, and performance metrics will be monitored during a standardized cycling exercise protocol.
This phase provides the dense mechanistic data required to refine a mathematical model of the placebo effect, offering insights into how individual personality traits and cognitive anchoring influence psychophysiological potential.
Panoramica dello studio
Stato
Non ancora reclutamento
Intervento / Trattamento
Descrizione dettagliata
This study employs a randomized, double-blind, placebo-controlled crossover design to conduct a multifactorial analysis of psychophysiological and biomechanical dynamics.
Participants (n = 80, aged 20-35 years) will complete four experimental sessions separated by 7-day washout periods, involving caffeine (6 mg/kg) or placebo administration.
The laboratory protocol (160 minutes) integrates multiple modalities: (1) cognitive testing (Reaction Time Test and Flanker Test), (2) postural control assessment using the BTrackS Balance Plate, and (3) a standardized cycle ergometer exercise protocol consisting of 15 minutes at the anaerobic threshold followed by a 5-minute self-paced maximal effort trial.
Belief manipulation (immediate vs. retrospective reporting) and cognitive anchoring (feedback conditions) are implemented to isolate expectancy-driven effects.
Continuous metabolic and cardiorespiratory data collected using the Cosmed K5 system will be synchronized with blood biomarkers (lactate, glucose, caffeine, and paraxanthine) and salivary biomarkers (cortisol, testosterone, and alpha-amylase).
Advanced statistical methods, including Functional Data Analysis (FDA) and machine learning, will be used to integrate physiological trajectories with behavioral predictors.
Tipo di studio
Interventistico
Iscrizione (Stimato)
80
Fase
- Non applicabile
Contatti e Sedi
Questa sezione fornisce i recapiti di coloro che conducono lo studio e informazioni su dove viene condotto lo studio.
Contatto studio
- Nome: Jakub Malik, PhD
- Numero di telefono: +48739975701
- Email: malik@awf.poznan.pl
Luoghi di studio
-
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Wielkopolska
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Poznan, Wielkopolska, Polonia
- Poznań University of Physical Education
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Contatto:
- Jakub Malik, PhD
- Numero di telefono: +48739975701
- Email: malik@awf.poznan.pl
-
-
Criteri di partecipazione
I ricercatori cercano persone che corrispondano a una certa descrizione, chiamata criteri di ammissibilità. Alcuni esempi di questi criteri sono le condizioni generali di salute di una persona o trattamenti precedenti.
Criteri di ammissibilità
Età idonea allo studio
- Adulto
Accetta volontari sani
Sì
Descrizione
Inclusion Criteria:
- Age between 20 and 35 years,
- Healthy adults,
- Regular physical activity, but not professional athletes,
- 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.
Piano di studio
Questa sezione fornisce i dettagli del piano di studio, compreso il modo in cui lo studio è progettato e ciò che lo studio sta misurando.
Come è strutturato lo studio?
Dettagli di progettazione
- Scopo principale: Scienza basilare
- Assegnazione: Randomizzato
- Modello interventistico: Assegnazione incrociata
- Mascheramento: Quadruplicare
Armi e interventi
Gruppo di partecipanti / Arm |
Intervento / Trattamento |
|---|---|
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Sperimentale: Sequence AABB
Participants follow the sequence: Caffeine, Caffeine, Placebo, Placebo, with a 7-day washout period between sessions.
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Anhydrous caffeine administered in an encapsulated form at a dosage of 6 mg per kilogram of body mass, 60 minutes before the exercise protocol.
Corn starch administered in an identical encapsulated form as the active caffeine, 60 minutes prior to the laboratory exercise protocol.
|
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Sperimentale: Sequence BBAA
Participants follow the sequence: Placebo, Placebo, Caffeine, Caffeine, with a 7-day washout period between sessions.
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Anhydrous caffeine administered in an encapsulated form at a dosage of 6 mg per kilogram of body mass, 60 minutes before the exercise protocol.
Corn starch administered in an identical encapsulated form as the active caffeine, 60 minutes prior to the laboratory exercise protocol.
|
|
Sperimentale: Sequence ABAB
Participants follow the sequence: Caffeine, Placebo, Caffeine, Placebo, with a 7-day washout period between sessions.
|
Anhydrous caffeine administered in an encapsulated form at a dosage of 6 mg per kilogram of body mass, 60 minutes before the exercise protocol.
Corn starch administered in an identical encapsulated form as the active caffeine, 60 minutes prior to the laboratory exercise protocol.
|
|
Sperimentale: Sequence BABA
Participants follow the sequence: Placebo, Caffeine, Placebo, Caffeine, with a 7-day washout period between sessions.
|
Anhydrous caffeine administered in an encapsulated form at a dosage of 6 mg per kilogram of body mass, 60 minutes before the exercise protocol.
Corn starch administered in an identical encapsulated form as the active caffeine, 60 minutes prior to the laboratory exercise protocol.
|
Cosa sta misurando lo studio?
Misure di risultato primarie
Misura del risultato |
Misura Descrizione |
Lasso di tempo |
|---|---|---|
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Physical Work Capacity (total work in J)
Lasso di tempo: Measured during each laboratory exercise protocol (approximately 85-120 minutes).
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Total physical work performed, expressed in Joules (J), during the standardized laboratory exercise protocol, including both the Anaerobic Threshold phase and the Self-paced Maximal Time-trial.
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Measured during each laboratory exercise protocol (approximately 85-120 minutes).
|
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Postural Control (mm)
Lasso di tempo: Measured continuously during the exercise protocol and at T1 (minute 2), T2 (minute 55), and T3 (minute 125).
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Center of Pressure excursions measured using the BTrackS Balance Plate and expressed in millimeters (mm).
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Measured continuously during the exercise protocol and at T1 (minute 2), T2 (minute 55), and T3 (minute 125).
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Explosive power variables (mm)
Lasso di tempo: Continuous recording throughout the exercise protocol and discrete assessments at T1 (2 minute of protocol), T2 (55 minute of protocol), and T3 (125 minute of protocol).
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Explosive lower-limb power expressed in millimeters (mm) - Countermovement Jump - height.
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Continuous recording throughout the exercise protocol and discrete assessments at T1 (2 minute of protocol), T2 (55 minute of protocol), and T3 (125 minute of protocol).
|
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Psychomotor Vigilance Test Reaction Time (ms)
Lasso di tempo: Measured at T1 (pre-ingestion, minute 2 of the protocol), T2 (post-ingestion/pre-exercise, minute 55 of the protocol), and T3 (post-exercise, minute 125 of the protocol).
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Reaction time during the Psychomotor Vigilance Test expressed in milliseconds (ms).
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Measured at T1 (pre-ingestion, minute 2 of the protocol), T2 (post-ingestion/pre-exercise, minute 55 of the protocol), and T3 (post-exercise, minute 125 of the protocol).
|
|
Flanker Test Reaction Time (ms)
Lasso di tempo: Measured at T1 (pre-ingestion, minute 2 of the protocol), T2 (post-ingestion/pre-exercise, minute 55 of the protocol), and T3 (post-exercise, minute 125 of the protocol).
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Reaction time during the Flanker Test expressed in milliseconds (ms).
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Measured at T1 (pre-ingestion, minute 2 of the protocol), T2 (post-ingestion/pre-exercise, minute 55 of the protocol), and T3 (post-exercise, minute 125 of the protocol).
|
Misure di risultato secondarie
Misura del risultato |
Misura Descrizione |
Lasso di tempo |
|---|---|---|
|
Exercise Heart Rate (bpm)
Lasso di tempo: Measured continuously during each laboratory exercise protocol (approximately 85-120 minutes).
|
Heart rate expressed in beats per minute (bpm) recorded continuously throughout the standardized laboratory exercise protocol.
|
Measured continuously during each laboratory exercise protocol (approximately 85-120 minutes).
|
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Exercise Heart Rate Variability (ms)
Lasso di tempo: Measured continuously during each laboratory exercise protocol (approximately 85-120 minutes).
|
Heart rate variability expressed in milliseconds (ms) and recorded continuously throughout the standardized laboratory exercise protocol to assess autonomic regulation.
|
Measured continuously during each laboratory exercise protocol (approximately 85-120 minutes).
|
|
Simple Reaction Time (ms)
Lasso di tempo: Measured at T1 (pre-ingestion, minute 2 of the protocol), T2 (post-ingestion/pre-exercise, minute 55 of the protocol), and T3 (post-exercise, minute 125 of the protocol).
|
Reaction time during the Simple Reaction Time test expressed in milliseconds (ms).
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Measured at T1 (pre-ingestion, minute 2 of the protocol), T2 (post-ingestion/pre-exercise, minute 55 of the protocol), and T3 (post-exercise, minute 125 of the protocol).
|
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Heart Rate Recovery (bpm)
Lasso di tempo: Measured continuously during the first 5 minutes immediately following exercise cessation.
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Heart rate recorded during the post-exercise recovery period, expressed in beats per minute (bpm).
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Measured continuously during the first 5 minutes immediately following exercise cessation.
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Rating of Perceived Exertion (Borg Scale, points)
Lasso di tempo: Before and immediately after warm-up, immediately after the Anaerobic Threshold phase, immediately after the Self-paced Maximal Time-trial, and immediately after cooldown during each laboratory study visit.
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Perceived exertion will be assessed using the Borg Rating of Perceived Exertion Scale and reported in points (6-20).
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Before and immediately after warm-up, immediately after the Anaerobic Threshold phase, immediately after the Self-paced Maximal Time-trial, and immediately after cooldown during each laboratory study visit.
|
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Personality Traits (NEO-FFI, points)
Lasso di tempo: Measured at baseline (first study visit).
|
Personality traits will be assessed using the NEO Five-Factor Inventory (NEO-FFI).
The questionnaire provides scores for five personality domains: Neuroticism, Extraversion, Openness to Experience, Agreeableness, and Conscientiousness.
Results will be reported as domain scores in points.
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Measured at baseline (first study visit).
|
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Mood State (POMS/BRUMS) (points)
Lasso di tempo: Measured during each laboratory study visit.
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Mood state assessed using the Profile of Mood States (POMS/BRUMS), expressed in points.
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Measured during each laboratory study visit.
|
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Caffeine Expectancy (Caff-EQ-Brief) (points)
Lasso di tempo: Measured 30 minutes post-ingestion.
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Caffeine expectancy assessed using the Caffeine Expectancy Questionnaire-Brief (Caff-EQ-Brief), expressed in points.
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Measured 30 minutes post-ingestion.
|
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Urine pH
Lasso di tempo: Measured once prior to the start of each laboratory study visit.
|
Urine pH measured using a urine strip analyzer.
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Measured once prior to the start of each laboratory study visit.
|
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White blood cells count and differential (count/L)
Lasso di tempo: Measured at baseline (pre-supplementation), 30 minutes post-ingestion, before exercise, and 3 minutes post-exercise.
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Assessment of the hematological parameter will be performed from fingertip capillary blood collected before supplementation (baseline), 30 minutes post-ingestion, before exercise, and 3 minutes post-exercise.
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Measured at baseline (pre-supplementation), 30 minutes post-ingestion, before exercise, and 3 minutes post-exercise.
|
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White blood cells count and differential (%)
Lasso di tempo: Measured at baseline (pre-supplementation), 30 minutes post-ingestion, before exercise, and 3 minutes post-exercise.
|
Assessment of the hematological parameter will be performed from fingertip capillary blood collected before supplementation (baseline), 30 minutes post-ingestion, before exercise, and 3 minutes post-exercise.
|
Measured at baseline (pre-supplementation), 30 minutes post-ingestion, before exercise, and 3 minutes post-exercise.
|
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Hematological indices (red blood cells, RBC) (count/L)
Lasso di tempo: Measured at baseline (pre-supplementation), 30 minutes post-ingestion, before exercise, and 3 minutes post-exercise.
|
Assessment of the hematological parameter will be performed from fingertip capillary blood collected before supplementation (baseline), 30 minutes post-ingestion, before exercise, and 3 minutes post-exercise.
|
Measured at baseline (pre-supplementation), 30 minutes post-ingestion, before exercise, and 3 minutes post-exercise.
|
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Hematological indices (hemoglobin concentration, HGB) (mmol/L)
Lasso di tempo: Measured at baseline (pre-supplementation), 30 minutes post-ingestion, before exercise, and 3 minutes post-exercise.
|
Assessment of the hematological parameter will be performed from fingertip capillary blood collected before supplementation (baseline), 30 minutes post-ingestion, before exercise, and 3 minutes post-exercise.
|
Measured at baseline (pre-supplementation), 30 minutes post-ingestion, before exercise, and 3 minutes post-exercise.
|
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Hematological indices (hematocrit, HCT) (L/L)
Lasso di tempo: Measured at baseline (pre-supplementation), 30 minutes post-ingestion, before exercise, and 3 minutes post-exercise.
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Assessment of the hematological parameter will be performed from fingertip capillary blood collected before supplementation (baseline), 30 minutes post-ingestion, before exercise, and 3 minutes post-exercise.
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Measured at baseline (pre-supplementation), 30 minutes post-ingestion, before exercise, and 3 minutes post-exercise.
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Hematological indices (mean corpuscular volume, MCV; mean platelet volume, MPV) (fL)
Lasso di tempo: Measured at baseline (pre-supplementation), 30 minutes post-ingestion, before exercise, and 3 minutes post-exercise.
|
Assessment of the hematological parameter will be performed from fingertip capillary blood collected before supplementation (baseline), 30 minutes post-ingestion, before exercise, and 3 minutes post-exercise.
|
Measured at baseline (pre-supplementation), 30 minutes post-ingestion, before exercise, and 3 minutes post-exercise.
|
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Hematological indices (mean corpuscular hemoglobin mass, MCH) (fmol)
Lasso di tempo: Measured at baseline (pre-supplementation), 30 minutes post-ingestion, before exercise, and 3 minutes post-exercise.
|
Assessment of the hematological parameter will be performed from fingertip capillary blood collected before supplementation (baseline), 30 minutes post-ingestion, before exercise, and 3 minutes post-exercise.
|
Measured at baseline (pre-supplementation), 30 minutes post-ingestion, before exercise, and 3 minutes post-exercise.
|
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Hematological indices (mean corpuscular hemoglobin concentration, MCHC) (mmol/L)
Lasso di tempo: Measured at baseline (pre-supplementation), 30 minutes post-ingestion, before exercise, and 3 minutes post-exercise.
|
Assessment of the hematological parameter will be performed from fingertip capillary blood collected before supplementation (baseline), 30 minutes post-ingestion, before exercise, and 3 minutes post-exercise.
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Measured at baseline (pre-supplementation), 30 minutes post-ingestion, before exercise, and 3 minutes post-exercise.
|
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Hematological indices (platelet count, PLT) (count/L)
Lasso di tempo: Measured at baseline (pre-supplementation), 30 minutes post-ingestion, before exercise, and 3 minutes post-exercise.
|
Assessment of the hematological parameter will be performed from fingertip capillary blood collected before supplementation (baseline), 30 minutes post-ingestion, before exercise, and 3 minutes post-exercise.
|
Measured at baseline (pre-supplementation), 30 minutes post-ingestion, before exercise, and 3 minutes post-exercise.
|
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Hematological indices (platelet hematocrit, PCT) (cL/L)
Lasso di tempo: Measured at baseline (pre-supplementation), 30 minutes post-ingestion, before exercise, and 3 minutes post-exercise.
|
Assessment of the hematological parameter will be performed from fingertip capillary blood collected before supplementation (baseline), 30 minutes post-ingestion, before exercise, and 3 minutes post-exercise.
|
Measured at baseline (pre-supplementation), 30 minutes post-ingestion, before exercise, and 3 minutes post-exercise.
|
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Hematological indices (platelet distribution width, PDW; platelet large cell ratio, PLCR; red blood cells distribution width - coefficient of variation, RDW-C) (%)
Lasso di tempo: Measured at baseline (pre-supplementation), 30 minutes post-ingestion, before exercise, and 3 minutes post-exercise.
|
Assessment of the hematological parameter will be performed from fingertip capillary blood collected before supplementation (baseline), 30 minutes post-ingestion, before exercise, and 3 minutes post-exercise.
|
Measured at baseline (pre-supplementation), 30 minutes post-ingestion, before exercise, and 3 minutes post-exercise.
|
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Hematological indices (red blood cells distribution width - standard deviation, RDW-S) (fL)
Lasso di tempo: Measured at baseline (pre-supplementation), 30 minutes post-ingestion, before exercise, and 3 minutes post-exercise.
|
Assessment of the hematological parameter will be performed from fingertip capillary blood collected before supplementation (baseline), 30 minutes post-ingestion, before exercise, and 3 minutes post-exercise.
|
Measured at baseline (pre-supplementation), 30 minutes post-ingestion, before exercise, and 3 minutes post-exercise.
|
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Urea Concentration (mmol/L)
Lasso di tempo: Measured at baseline (pre-supplementation), 30 minutes post-ingestion, before exercise, and 3 minutes post-exercise.
|
Urea concentration measured from fingertip capillary blood and expressed in mmol/L.
|
Measured at baseline (pre-supplementation), 30 minutes post-ingestion, before exercise, and 3 minutes post-exercise.
|
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Glucose Concentration (mg/dL)
Lasso di tempo: Measured at baseline (pre-supplementation), 30 minutes post-ingestion, before exercise, and 3 minutes post-exercise.
|
Glucose concentration measured from fingertip capillary blood and expressed in mg/dL.
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Measured at baseline (pre-supplementation), 30 minutes post-ingestion, before exercise, and 3 minutes post-exercise.
|
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Creatinine concentration (μmol/L)
Lasso di tempo: Measured at baseline (pre-supplementation), 30 minutes post-ingestion, before exercise, and 3 minutes post-exercise.
|
Creatinine concentration measured from fingertip capillary blood and expressed in µmol/L.
|
Measured at baseline (pre-supplementation), 30 minutes post-ingestion, before exercise, and 3 minutes post-exercise.
|
|
Muscle damage markers (activity of alanine aminotransferase, aspartate aminotransferase, creatine kinase, lactate dehydrogenase) (U/L)
Lasso di tempo: Measured at baseline (pre-supplementation), 30 minutes post-ingestion, before exercise, and 3 minutes post-exercise.
|
Assessment of the muscle damage markers (activity of alanine aminotransferase, aspartate aminotransferase, creatine kinase, lactate dehydrogenase) (U/L) will be performed from fingertip capillary blood.
|
Measured at baseline (pre-supplementation), 30 minutes post-ingestion, before exercise, and 3 minutes post-exercise.
|
|
Lactate concentration (mmol/L)
Lasso di tempo: Measured at baseline (pre-supplementation), 30 minutes post-ingestion, before exercise, and 3 minutes post-exercise.
|
Blood lactate concentration measured from fingertip capillary blood and expressed in mmol/L.
|
Measured at baseline (pre-supplementation), 30 minutes post-ingestion, before exercise, and 3 minutes post-exercise.
|
|
Electrolites' concentration (Ca, Na, K, Cl) (mmol/L)
Lasso di tempo: Measured at baseline (pre-supplementation), 30 minutes post-ingestion, before exercise, and 3 minutes post-exercise.
|
Assessment of electrolites' concentration (Ca, Na, K, Cl) (mmol/L) will be performed from fingertip capillary blood.
|
Measured at baseline (pre-supplementation), 30 minutes post-ingestion, before exercise, and 3 minutes post-exercise.
|
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Blood pH
Lasso di tempo: Measured at baseline (pre-supplementation), 30 minutes post-ingestion, before exercise, and 3 minutes post-exercise.
|
Assessment of gasometry markers (blood pH) will be performed from fingertip capillary blood.
|
Measured at baseline (pre-supplementation), 30 minutes post-ingestion, before exercise, and 3 minutes post-exercise.
|
|
Partial Pressure of Carbon Dioxide and Oxygen (pCO2, pO2) (mmHg)
Lasso di tempo: Measured at baseline (pre-supplementation), 30 minutes post-ingestion, before exercise, and 3 minutes post-exercise.
|
Assessment of gasometry markers (pCO2, pO2) (mmHg) will be performed from fingertip capillary blood.
|
Measured at baseline (pre-supplementation), 30 minutes post-ingestion, before exercise, and 3 minutes post-exercise.
|
|
CAF and PAX concentrations (µmol/L)
Lasso di tempo: Measured at baseline (pre-supplementation), 30 minutes post-ingestion, before exercise, and 3 minutes post-exercise.
|
Assessment of caffeine and paraxanthine concentrations (µmol/L) will be performed from fingertip capillary blood.
|
Measured at baseline (pre-supplementation), 30 minutes post-ingestion, before exercise, and 3 minutes post-exercise.
|
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Static weight distribution (mm)
Lasso di tempo: Measured at the start of each study visit.
|
Static weight distribution expressed in millimeters of Center of Pressure symmetry.
|
Measured at the start of each study visit.
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Analysis of body composition (fat-free mass, fat mass) (kg)
Lasso di tempo: Measured at the start of each study visit.
|
Assessment of body composition (fat-free mass, fat mass) (kg) will be carried out at the start of each study visit.
|
Measured at the start of each study visit.
|
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Analysis of body composition (total body water) (L)
Lasso di tempo: Measured at the start of each study visit.
|
Assessment of body composition (total body water) (L) will be carried out at the start of each study visit.
|
Measured at the start of each study visit.
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Analysis of body composition (total body water) (%)
Lasso di tempo: Measured at the start of each study visit.
|
Assessment of body composition (total body water) (%) will be carried out at the start of each study visit.
|
Measured at the start of each study visit.
|
|
Autonomic Response during Cognitive Performance (bpm)
Lasso di tempo: Measured at three time points: T1 (pre-ingestion; 2 minute of protocol), T2 (post-ingestion/pre-exercise; 55 minute of protocol), and T3 (post-exercise; 125 minute of protocol).
|
Heart rate and heart rate variability recording during cognitive testing blocks, expressed in beats per minute (bpm).
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Measured at three time points: T1 (pre-ingestion; 2 minute of protocol), T2 (post-ingestion/pre-exercise; 55 minute of protocol), and T3 (post-exercise; 125 minute of protocol).
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Anthropometric Indices (kg)
Lasso di tempo: Measured at the start of each study visit.
|
Body mass in kilograms will be measured at the start of each study visit.
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Measured at the start of each study visit.
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Anthropometric Indices (metres)
Lasso di tempo: Measured at the start of each study visit.
|
Height in metres will be measured at the start of each study visit.
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Measured at the start of each study visit.
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Explosive power variables (ms)
Lasso di tempo: Continuous recording throughout the exercise protocol and discrete assessments at T1 (2 minute of protocol), T2 (55 minute of protocol), and T3 (125 minute of protocol).
|
Explosive lower-limb power variables expressed in milliseconds (ms) - Countermovement Jump - contact time and flight time.
|
Continuous recording throughout the exercise protocol and discrete assessments at T1 (2 minute of protocol), T2 (55 minute of protocol), and T3 (125 minute of protocol).
|
|
Explosive power variables (W)
Lasso di tempo: Continuous recording throughout the exercise protocol and discrete assessments at T1 (2 minute of protocol), T2 (55 minute of protocol), and T3 (125 minute of protocol).
|
Explosive lower-limb power expressed in Watts (W) - Countermovement Jump - power.
|
Continuous recording throughout the exercise protocol and discrete assessments at T1 (2 minute of protocol), T2 (55 minute of protocol), and T3 (125 minute of protocol).
|
|
Hydration Status (g/mL)
Lasso di tempo: Once prior to the start of each laboratory study visit.
|
Assessment of urine specific gravity (g/mL) using a urine strip analyzer.
|
Once prior to the start of each laboratory study visit.
|
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Flanker Test Accuracy (%)
Lasso di tempo: Measured at T1 (pre-ingestion, minute 2 of the protocol), T2 (post-ingestion/pre-exercise, minute 55 of the protocol), and T3 (post-exercise, minute 125 of the protocol).
|
Accuracy during the Flanker Test expressed as the percentage of correct responses.
|
Measured at T1 (pre-ingestion, minute 2 of the protocol), T2 (post-ingestion/pre-exercise, minute 55 of the protocol), and T3 (post-exercise, minute 125 of the protocol).
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Heart Rate Variability Recovery (ms)
Lasso di tempo: Measured continuously during the first 5 minutes immediately following exercise cessation.
|
Heart rate variability expressed in milliseconds (ms) during the post-exercise recovery period.
|
Measured continuously during the first 5 minutes immediately following exercise cessation.
|
|
Caffeine Expectancy Questionnaire Score (points)
Lasso di tempo: Measured 30 minutes post-ingestion.
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Caffeine expectancy assessed using the Caffeine Expectancy Questionnaire and expressed in points.
|
Measured 30 minutes post-ingestion.
|
|
Suggestibility (SSS) (points)
Lasso di tempo: Measured during the last study visit.
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General suggestibility assessed using the Short Suggestibility Scale (SSS), expressed in points.
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Measured during the last study visit.
|
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Intrinsic Motivation (IMI) (points)
Lasso di tempo: Measured after each test block during every laboratory study visit.
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Task-specific intrinsic motivation assessed using the Intrinsic Motivation Inventory (IMI), expressed in points.
|
Measured after each test block during every laboratory study visit.
|
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Sport Motivation (SMS) (points)
Lasso di tempo: Measured during the first study visit.
|
Sport motivation assessed using the Sport Motivation Scale (SMS), expressed in points.
|
Measured during the first study visit.
|
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Sleep Quality (LSEQ) (points)
Lasso di tempo: Measured once during each laboratory study visit.
|
Subjective sleep quality assessed using the Leeds Sleep Evaluation Questionnaire (LSEQ), expressed in points.
|
Measured once during each laboratory study visit.
|
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Salivary Cortisol Concentration (nmol/L)
Lasso di tempo: Measured at baseline (pre-supplementation), 30 minutes post-ingestion, before warm-up (60 minutes post-ingestion), 3 minutes post-exercise, and 10 minutes post-exercise.
|
Salivary cortisol concentration expressed in nmol/L.
|
Measured at baseline (pre-supplementation), 30 minutes post-ingestion, before warm-up (60 minutes post-ingestion), 3 minutes post-exercise, and 10 minutes post-exercise.
|
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Salivary Testosterone Concentration (pmol/L)
Lasso di tempo: Measured at baseline (pre-supplementation), 30 minutes post-ingestion, before warm-up (60 minutes post-ingestion), 3 minutes post-exercise, and 10 minutes post-exercise.
|
Salivary testosterone concentration expressed in pmol/L.
|
Measured at baseline (pre-supplementation), 30 minutes post-ingestion, before warm-up (60 minutes post-ingestion), 3 minutes post-exercise, and 10 minutes post-exercise.
|
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Salivary Alpha-amylase Activity (U/L)
Lasso di tempo: Measured at baseline (pre-supplementation), 30 minutes post-ingestion, before warm-up (60 minutes post-ingestion), 3 minutes post-exercise, and 10 minutes post-exercise.
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Salivary alpha-amylase activity expressed in U/L.
|
Measured at baseline (pre-supplementation), 30 minutes post-ingestion, before warm-up (60 minutes post-ingestion), 3 minutes post-exercise, and 10 minutes post-exercise.
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Collaboratori e investigatori
Qui è dove troverai le persone e le organizzazioni coinvolte in questo studio.
Investigatori
- Investigatore principale: Jakub Malik, PhD, Poznan University of Physical Education, Department of Sports Psychology
Studiare le date dei record
Queste date tengono traccia dell'avanzamento della registrazione dello studio e dell'invio dei risultati di sintesi a ClinicalTrials.gov. I record degli studi e i risultati riportati vengono esaminati dalla National Library of Medicine (NLM) per assicurarsi che soddisfino specifici standard di controllo della qualità prima di essere pubblicati sul sito Web pubblico.
Studia le date principali
Inizio studio (Stimato)
1 gennaio 2027
Completamento primario (Stimato)
31 marzo 2028
Completamento dello studio (Stimato)
31 marzo 2029
Date di iscrizione allo studio
Primo inviato
21 luglio 2026
Primo inviato che soddisfa i criteri di controllo qualità
31 luglio 2026
Primo Inserito (Effettivo)
5 agosto 2026
Aggiornamenti dei record di studio
Ultimo aggiornamento pubblicato (Effettivo)
18 settembre 2026
Ultimo aggiornamento inviato che soddisfa i criteri QC
15 settembre 2026
Ultimo verificato
1 luglio 2026
Maggiori informazioni
Termini relativi a questo studio
Parole chiave
Termini MeSH pertinenti aggiuntivi
Altri numeri di identificazione dello studio
- 152-2-26
- 2025/57/N/NZ4/04470 (Altro numero di sovvenzione/finanziamento: National Science Centre)
Piano per i dati dei singoli partecipanti (IPD)
Hai intenzione di condividere i dati dei singoli partecipanti (IPD)?
SÌ
Descrizione del piano IPD
The study protocol will be published as an open-access article.
Upon completion of the study, de-identified individual participant data (IPD) and relevant analytic code will be deposited in an open-access repository such as Zenodo or OSF, following the FAIR principles.
Periodo di condivisione IPD
The study protocol will be available upon its publication.
The IPD and analytic code will be available starting from the date of the primary study results publication and will remain accessible for at least 5 years.
Criteri di accesso alla condivisione IPD
The study protocol will be published as an open-access article.
Upon completion of the study, de-identified individual participant data (IPD) and relevant analytic code will be deposited in an open-access repository such as Zenodo or OSF, in accordance with FAIR principles.
Tipo di informazioni di supporto alla condivisione IPD
- STUDIO_PROTOCOLLO
Informazioni su farmaci e dispositivi, documenti di studio
Studia un prodotto farmaceutico regolamentato dalla FDA degli Stati Uniti
No
Studia un dispositivo regolamentato dalla FDA degli Stati Uniti
No
Queste informazioni sono state recuperate direttamente dal sito web clinicaltrials.gov senza alcuna modifica. In caso di richieste di modifica, rimozione o aggiornamento dei dettagli dello studio, contattare register@clinicaltrials.gov. Non appena verrà implementata una modifica su clinicaltrials.gov, questa verrà aggiornata automaticamente anche sul nostro sito web .