About this trial
The study investigates whether repeated exposure to cold showers can improve the ability to cope with and respond to stress. In particular, it examines both the psychophysiological effects of cold showers and the role of expectations regarding their effectiveness. The research adopts a 2×2 experimental design with approximately 120 healthy adults, randomly assigned to either an experimental group or a control group, and further divided based on the presence or absence of information emphasizing the potential benefits of the intervention. The experimental group takes warm or lukewarm showers with a final 30-second exposure to cold water at least four times per week, while the control group takes only warm or lukewarm showers. In parallel, some participants receive positive information about the effectiveness of the intervention for stress management, while others receive no specific information. At baseline and at the end of the study, participants complete questionnaires assessing perceived stress, psychological well-being, and quality of life, along with a physiological measure and a cognitive stress task (Stroop test with heart rate monitoring). During the four-week intervention period, participants keep a daily diary recording shower habits and perceived stress levels.
Eligibility criteria
Qualifiers
Age ≥ 18 years
Good general health status, self-reported and/or certified by a medical document (e.g., general medical certificate or sports medical clearance)
Willingness to participate for the full duration of the study (4 weeks)
Ability to understand and independently complete questionnaires and study diaries
Disqualifiers
Uncompensated cardiovascular, neurological, or endocrine conditions considered relevant to stress or cold exposure tolerance
Medical conditions contraindicating cold exposure (e.g., Raynaud's phenomenon, cold urticaria, etc.)
Pregnancy
Use of medications that may interfere with stress responses (e.g., beta-blockers, anxiolytics, systemic corticosteroids)
Trial design
Treatments tested in this trial
- Positive expectation about the effects of cold and warm showers
- No expectation regarding the exposure to cold water and/or to warm showers