Hemodynamic Effects of Dry Sauna Followed by Cold Water Immersion in Healthy Subjects

Study Overview
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Brief Summary
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The purpose of this study is to determine the safety on sauna followed by cold water bath, a common practice in many countries, 30 healthy subjects aged 40 years and older will be at the Montreal Heart Institute Prevention and Cardiac Rehabilitation centre.

Detailed Description
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To determine the safety on sauna followed by cold water bath, a common practice in many countries, 30 healthy subjects aged 40 years and older will be at the Montreal Heart Institute Prevention and Cardiac Rehabilitation centre. A recent complete evaluation will have excluded any cardiac condition. Subjects will first spend 10 minutes in a dry sauna at 85 degrees celtius. Immediately after , subjects will be immersed in a cold water bath (ICool , Australia) at a temperature of 5 degrees celtius for approximately one minute. Blood pressure , ecg , gaz exchange and thoracic impedance will be measured during sauna and cold water bath. Principal goal of study: to determine the safety of this practice. Secondary goals of study: to measure the blood pressure response, heart rate, presence of arrythmyas, cardiac output and cerebral perfusion during both conditions. Primary endpoint: Change in systolic blood pressure from sauna (after 10 minutes ) to cold water (after one minute). Physiologic measurements: continuous ECG monitoring, BP measurements at every 3 minutes during sauna and at one minute in the cold bath, gaz exchange with a portable equipment (Cosmed K4), bioimpedance and cerebral perfusion with a single frontal NIRS electrode.

Official Title
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Hemodynamic Effects of Dry Sauna Followed by Cold Water Immersion in Healthy Subjects

Conditions
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Blood Pressure, Arrhythmias

Intervention / Treatment
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* Other: Sauna and cold water bath


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Healthy women and men aged 40 and older with a recent complete medical evaluation including a normal resting ECG and a normal symptom-limited treadmill exercise test. Exclusion Criteria: Any cardiac condition, abnormal exercise test, hypertension, type I diabetes and presence of any medications that may affect blood pressure.

Ages Eligible for Study
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Minimum Age: 40 Years
Maximum Age: 80 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Prevention
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Sauna + Cold Water Bath<br>Subjects will first spend 10 minutes in a dry sauna at 85 degrees celtius. Immediately after , subjects will be immersed in a cold water bath (ICool , Australia) at a temperature of 5 degrees celtius for approximately one minute. Blood pressure , ecg , gaz exchange and thoracic impedance will be measured during sauna and cold water bath. | Other: Sauna and cold water bath<br>* Subjects will first spend 10 minutes in a dry sauna at 85 degrees celtius. Immediately after, subjects will be immersed in a cold water bath (ICool , Australia) at a temperature of 5 degrees celtius for approximately one minute. Blood pressure , ecg , gaz exchange and thoracic impedance will be measured during sauna and cold water bath.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Blood pressure |  | Difference between baseline and 11 minutes of intervention. | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Arrhytmias | Patients will use a HOLTER during all experiment. Total time: 25 minutes. | Number of arrhytmias during all 25 minutes of the intervention. | 
| Blood pressure |  | Measured at 10 minutes after the end of the intervention (recovery period). | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Cold water bath, Sauna