Placebo Effect on Cycling Performance: Laboratory Crossover Study
Ориентир для пациента и семьи
Простыми словами
Автоматическая сводка по структурированным данным реестра. Она помогает сориентироваться, но не заменяет официальный протокол или оценку врача.
- Что изучают
- В протоколе указаны: Caffeine (6mg/kg), Placebo (Starch capsule).
- Кому может быть актуально
- Состояния в реестре: Physical Performance, Placebo Effect, Cognitive Performance. Базовые параметры: 20 лет — 30 лет · Все.
- Что важно проверить
- Возраст, диагноз и пол — только базовые ориентиры. Предыдущее лечение, анализы и другие обязательные условия указаны ниже в критериях участия.
- Где проводится
- Польша
- Следующий шаг
- Сохраните исследование, покажите его лечащему врачу и уточните актуальный статус у исследовательского центра. Расходы, документы и поездка →
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Официальное название
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
Обзор
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.
Подробное описание
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.
Вмешательства
- Препарат Caffeine (6mg/kg)
Anhydrous caffeine administered in an encapsulated form at a dosage of 6 mg per kilogram of body mass, 60 minutes before the exercise protocol. - Другое Placebo (Starch capsule)
Corn starch administered in an identical encapsulated form as the active caffeine, 60 minutes prior to the laboratory exercise protocol.
Первичные конечные точки
- Physical Work Capacity (total work in J) [Срок оценки: Measured during each laboratory exercise protocol (approximately 85-120 minutes).]
Вторичные конечные точки (12)
- Exercise Heart Rate (bpm) [Срок оценки: Measured continuously during each laboratory exercise protocol (approximately 85-120 minutes).]
- Exercise Heart Rate Variability (ms) [Срок оценки: Measured continuously during each laboratory exercise protocol (approximately 85-120 minutes).]
- Salivary Cortisol Concentration (nmol/L) [Срок оценки: Measured at baseline (pre-supplementation), 30 minutes post-ingestion, after warm-up (60 minutes post-ingestion), and 3 minutes post-exercise.]
- Salivary Testosterone Concentration (pmol/L) [Срок оценки: Measured at baseline (pre-supplementation), 30 minutes post-ingestion, after warm-up (60 minutes post-ingestion), and 3 minutes post-exercise.]
- Salivary Alpha-amylase Activity (U/L) [Срок оценки: Measured at baseline (pre-supplementation), 30 minutes post-ingestion, after warm-up (60 minutes post-ingestion), and 3 minutes post-exercise.]
- Simple Reaction Time (ms) [Срок оценки: 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).]
- Heart Rate Recovery (bpm) [Срок оценки: Measured continuously during the first 5 minutes immediately following exercise cessation.]
- Postural Control (mm) [Срок оценки: Measured continuously during the exercise protocol and at T1 (minute 2), T2 (minute 55), and T3 (minute 125).]
- Rating of Perceived Exertion (Borg Scale, points) [Срок оценки: 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.]
- Personality Traits (NEO-FFI, points) [Срок оценки: Measured at baseline (first study visit).]
- Mood State (POMS/BRUMS) (points) [Срок оценки: Measured during each laboratory study visit.]
- Caffeine Expectancy (Caff-EQ-Brief) (points) [Срок оценки: Measured 30 minutes post-ingestion.]
Критерии участия
Критерии включения
- Age between 20 and 30 years,
- Healthy adults,
- Regular physical activity, but not professional athletes,
- Normal or corrected-to-normal vision,
- Habitual caffeine consumption.
Критерии исключения
- 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.
Критерии приведены из реестра в оригинале (на английском). Окончательную оценку соответствия проводит исследовательский центр.
Здоровые добровольцы: Да
Дизайн исследования
- Распределение
- Рандомизированное
- Модель
- Перекрёстный дизайн
- Маскирование
- Четверное слепое
- Основная цель
- Фундаментальное исследование
Центры проведения
Польша · 1 центр
- Poznan University of Physical Education — Poznan
Идентификаторы
NCT: NCT07748429 · 152-2-26 · 2025/57/N/NZ4/04470