Placebo Effect on Cycling Performance: Laboratory Crossover Study
15 de septiembre de 2026 actualizado por: 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.
Descripción general del estudio
Estado
Aún no reclutando
Condiciones
Intervención / Tratamiento
Descripción detallada
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 de estudio
Intervencionista
Inscripción (Estimado)
80
Fase
- No aplica
Contactos y Ubicaciones
Esta sección proporciona los datos de contacto de quienes realizan el estudio e información sobre dónde se lleva a cabo este estudio.
Estudio Contacto
- Nombre: Jakub Malik, PhD
- Número de teléfono: +48739975701
- Correo electrónico: malik@awf.poznan.pl
Ubicaciones de estudio
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Wielkopolska
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Poznan, Wielkopolska, Polonia
- Poznań University of Physical Education
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Contacto:
- Jakub Malik, PhD
- Número de teléfono: +48739975701
- Correo electrónico: malik@awf.poznan.pl
-
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Criterios de participación
Los investigadores buscan personas que se ajusten a una determinada descripción, denominada criterio de elegibilidad. Algunos ejemplos de estos criterios son el estado de salud general de una persona o tratamientos previos.
Criterio de elegibilidad
Edades elegibles para estudiar
- Adulto
Acepta Voluntarios Saludables
Sí
Descripción
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.
Plan de estudios
Esta sección proporciona detalles del plan de estudio, incluido cómo está diseñado el estudio y qué mide el estudio.
¿Cómo está diseñado el estudio?
Detalles de diseño
- Propósito principal: Ciencia básica
- Asignación: Aleatorizado
- Modelo Intervencionista: Asignación cruzada
- Enmascaramiento: Cuadruplicar
Armas e Intervenciones
Grupo de participantes/brazo |
Intervención / Tratamiento |
|---|---|
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Experimental: 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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Experimental: 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.
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Experimental: Sequence ABAB
Participants follow the sequence: Caffeine, Placebo, Caffeine, 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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Experimental: 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.
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¿Qué mide el estudio?
Medidas de resultado primarias
Medida de resultado |
Medida Descripción |
Periodo de tiempo |
|---|---|---|
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Physical Work Capacity (total work in J)
Periodo de tiempo: 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)
Periodo de tiempo: 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)
Periodo de tiempo: 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)
Periodo de tiempo: 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).
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Flanker Test Reaction Time (ms)
Periodo de tiempo: 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).
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Medidas de resultado secundarias
Medida de resultado |
Medida Descripción |
Periodo de tiempo |
|---|---|---|
|
Exercise Heart Rate (bpm)
Periodo de tiempo: Measured continuously during each laboratory exercise protocol (approximately 85-120 minutes).
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Heart rate expressed in beats per minute (bpm) recorded continuously throughout the standardized laboratory exercise protocol.
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Measured continuously during each laboratory exercise protocol (approximately 85-120 minutes).
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Exercise Heart Rate Variability (ms)
Periodo de tiempo: Measured continuously during each laboratory exercise protocol (approximately 85-120 minutes).
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Heart rate variability expressed in milliseconds (ms) and recorded continuously throughout the standardized laboratory exercise protocol to assess autonomic regulation.
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Measured continuously during each laboratory exercise protocol (approximately 85-120 minutes).
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Simple Reaction Time (ms)
Periodo de tiempo: 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 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)
Periodo de tiempo: 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)
Periodo de tiempo: 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)
Periodo de tiempo: Measured at baseline (first study visit).
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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)
Periodo de tiempo: 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)
Periodo de tiempo: 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
Periodo de tiempo: Measured once prior to the start of each laboratory study visit.
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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)
Periodo de tiempo: 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 (%)
Periodo de tiempo: 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 (red blood cells, RBC) (count/L)
Periodo de tiempo: 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 (hemoglobin concentration, HGB) (mmol/L)
Periodo de tiempo: 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 (hematocrit, HCT) (L/L)
Periodo de tiempo: 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)
Periodo de tiempo: 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 hemoglobin mass, MCH) (fmol)
Periodo de tiempo: 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 hemoglobin concentration, MCHC) (mmol/L)
Periodo de tiempo: 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 (platelet count, PLT) (count/L)
Periodo de tiempo: 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 (platelet hematocrit, PCT) (cL/L)
Periodo de tiempo: 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 (platelet distribution width, PDW; platelet large cell ratio, PLCR; red blood cells distribution width - coefficient of variation, RDW-C) (%)
Periodo de tiempo: 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 (red blood cells distribution width - standard deviation, RDW-S) (fL)
Periodo de tiempo: 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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Urea Concentration (mmol/L)
Periodo de tiempo: Measured at baseline (pre-supplementation), 30 minutes post-ingestion, before exercise, and 3 minutes post-exercise.
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Urea concentration measured from fingertip capillary blood and expressed in mmol/L.
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Measured at baseline (pre-supplementation), 30 minutes post-ingestion, before exercise, and 3 minutes post-exercise.
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Glucose Concentration (mg/dL)
Periodo de tiempo: Measured at baseline (pre-supplementation), 30 minutes post-ingestion, before exercise, and 3 minutes post-exercise.
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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)
Periodo de tiempo: Measured at baseline (pre-supplementation), 30 minutes post-ingestion, before exercise, and 3 minutes post-exercise.
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Creatinine concentration measured from fingertip capillary blood and expressed in µmol/L.
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Measured at baseline (pre-supplementation), 30 minutes post-ingestion, before exercise, and 3 minutes post-exercise.
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Muscle damage markers (activity of alanine aminotransferase, aspartate aminotransferase, creatine kinase, lactate dehydrogenase) (U/L)
Periodo de tiempo: Measured at baseline (pre-supplementation), 30 minutes post-ingestion, before exercise, and 3 minutes post-exercise.
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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.
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Measured at baseline (pre-supplementation), 30 minutes post-ingestion, before exercise, and 3 minutes post-exercise.
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Lactate concentration (mmol/L)
Periodo de tiempo: Measured at baseline (pre-supplementation), 30 minutes post-ingestion, before exercise, and 3 minutes post-exercise.
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Blood lactate concentration measured from fingertip capillary blood and expressed in mmol/L.
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Measured at baseline (pre-supplementation), 30 minutes post-ingestion, before exercise, and 3 minutes post-exercise.
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Electrolites' concentration (Ca, Na, K, Cl) (mmol/L)
Periodo de tiempo: Measured at baseline (pre-supplementation), 30 minutes post-ingestion, before exercise, and 3 minutes post-exercise.
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Assessment of electrolites' concentration (Ca, Na, K, Cl) (mmol/L) will be performed from fingertip capillary blood.
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Measured at baseline (pre-supplementation), 30 minutes post-ingestion, before exercise, and 3 minutes post-exercise.
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Blood pH
Periodo de tiempo: Measured at baseline (pre-supplementation), 30 minutes post-ingestion, before exercise, and 3 minutes post-exercise.
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Assessment of gasometry markers (blood pH) will be performed from fingertip capillary blood.
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Measured at baseline (pre-supplementation), 30 minutes post-ingestion, before exercise, and 3 minutes post-exercise.
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Partial Pressure of Carbon Dioxide and Oxygen (pCO2, pO2) (mmHg)
Periodo de tiempo: Measured at baseline (pre-supplementation), 30 minutes post-ingestion, before exercise, and 3 minutes post-exercise.
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Assessment of gasometry markers (pCO2, pO2) (mmHg) will be performed from fingertip capillary blood.
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Measured at baseline (pre-supplementation), 30 minutes post-ingestion, before exercise, and 3 minutes post-exercise.
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CAF and PAX concentrations (µmol/L)
Periodo de tiempo: Measured at baseline (pre-supplementation), 30 minutes post-ingestion, before exercise, and 3 minutes post-exercise.
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Assessment of caffeine and paraxanthine concentrations (µmol/L) will be performed from fingertip capillary blood.
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Measured at baseline (pre-supplementation), 30 minutes post-ingestion, before exercise, and 3 minutes post-exercise.
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Static weight distribution (mm)
Periodo de tiempo: Measured at the start of each study visit.
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Static weight distribution expressed in millimeters of Center of Pressure symmetry.
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Measured at the start of each study visit.
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Analysis of body composition (fat-free mass, fat mass) (kg)
Periodo de tiempo: Measured at the start of each study visit.
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Assessment of body composition (fat-free mass, fat mass) (kg) will be carried out at the start of each study visit.
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Measured at the start of each study visit.
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Analysis of body composition (total body water) (L)
Periodo de tiempo: Measured at the start of each study visit.
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Assessment of body composition (total body water) (L) will be carried out at the start of each study visit.
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Measured at the start of each study visit.
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Analysis of body composition (total body water) (%)
Periodo de tiempo: Measured at the start of each study visit.
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Assessment of body composition (total body water) (%) will be carried out at the start of each study visit.
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Measured at the start of each study visit.
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Autonomic Response during Cognitive Performance (bpm)
Periodo de tiempo: 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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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)
Periodo de tiempo: Measured at the start of each study visit.
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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)
Periodo de tiempo: Measured at the start of each study visit.
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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)
Periodo de tiempo: 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 variables expressed in milliseconds (ms) - Countermovement Jump - contact time and flight time.
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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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Explosive power variables (W)
Periodo de tiempo: 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 Watts (W) - Countermovement Jump - power.
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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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Hydration Status (g/mL)
Periodo de tiempo: Once prior to the start of each laboratory study visit.
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Assessment of urine specific gravity (g/mL) using a urine strip analyzer.
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Once prior to the start of each laboratory study visit.
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Flanker Test Accuracy (%)
Periodo de tiempo: 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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Accuracy during the Flanker Test expressed as the percentage of correct responses.
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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 Variability Recovery (ms)
Periodo de tiempo: Measured continuously during the first 5 minutes immediately following exercise cessation.
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Heart rate variability expressed in milliseconds (ms) during the post-exercise recovery period.
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Measured continuously during the first 5 minutes immediately following exercise cessation.
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Caffeine Expectancy Questionnaire Score (points)
Periodo de tiempo: Measured 30 minutes post-ingestion.
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Caffeine expectancy assessed using the Caffeine Expectancy Questionnaire and expressed in points.
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Measured 30 minutes post-ingestion.
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Suggestibility (SSS) (points)
Periodo de tiempo: 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)
Periodo de tiempo: 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.
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Measured after each test block during every laboratory study visit.
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Sport Motivation (SMS) (points)
Periodo de tiempo: Measured during the first study visit.
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Sport motivation assessed using the Sport Motivation Scale (SMS), expressed in points.
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Measured during the first study visit.
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Sleep Quality (LSEQ) (points)
Periodo de tiempo: Measured once during each laboratory study visit.
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Subjective sleep quality assessed using the Leeds Sleep Evaluation Questionnaire (LSEQ), expressed in points.
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Measured once during each laboratory study visit.
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Salivary Cortisol Concentration (nmol/L)
Periodo de tiempo: 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 cortisol concentration expressed in nmol/L.
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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)
Periodo de tiempo: 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 expressed in pmol/L.
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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)
Periodo de tiempo: 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.
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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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Colaboradores e Investigadores
Aquí es donde encontrará personas y organizaciones involucradas en este estudio.
Patrocinador
Investigadores
- Investigador principal: Jakub Malik, PhD, Poznan University of Physical Education, Department of Sports Psychology
Fechas de registro del estudio
Estas fechas rastrean el progreso del registro del estudio y los envíos de resultados resumidos a ClinicalTrials.gov. Los registros del estudio y los resultados informados son revisados por la Biblioteca Nacional de Medicina (NLM) para asegurarse de que cumplan con los estándares de control de calidad específicos antes de publicarlos en el sitio web público.
Fechas importantes del estudio
Inicio del estudio (Estimado)
1 de enero de 2027
Finalización primaria (Estimado)
31 de marzo de 2028
Finalización del estudio (Estimado)
31 de marzo de 2029
Fechas de registro del estudio
Enviado por primera vez
21 de julio de 2026
Primero enviado que cumplió con los criterios de control de calidad
31 de julio de 2026
Publicado por primera vez (Actual)
5 de agosto de 2026
Actualizaciones de registros de estudio
Última actualización publicada (Actual)
18 de septiembre de 2026
Última actualización enviada que cumplió con los criterios de control de calidad
15 de septiembre de 2026
Última verificación
1 de julio de 2026
Más información
Términos relacionados con este estudio
Palabras clave
Términos MeSH relevantes adicionales
Otros números de identificación del estudio
- 152-2-26
- 2025/57/N/NZ4/04470 (Otro número de subvención/financiamiento: National Science Centre)
Plan de datos de participantes individuales (IPD)
¿Planea compartir datos de participantes individuales (IPD)?
SÍ
Descripción del plan 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.
Marco de tiempo para compartir 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.
Criterios de acceso compartido de 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 de información de apoyo para compartir IPD
- PROTOCOLO DE ESTUDIO
Información sobre medicamentos y dispositivos, documentos del estudio
Estudia un producto farmacéutico regulado por la FDA de EE. UU.
No
Estudia un producto de dispositivo regulado por la FDA de EE. UU.
No
Esta información se obtuvo directamente del sitio web clinicaltrials.gov sin cambios. Si tiene alguna solicitud para cambiar, eliminar o actualizar los detalles de su estudio, comuníquese con register@clinicaltrials.gov. Tan pronto como se implemente un cambio en clinicaltrials.gov, también se actualizará automáticamente en nuestro sitio web. .