By Professor Marc Cohen, Board Member of the Global Wellness Summit, Co-founder of the Bathe the World Foundation and Founder of the Extreme Wellness Institute.
Hydro-thermal therapies such as hot baths, cold plunges, saunas, steambaths and mud-wraps improve public health, reduce the risk of chronic disease and boost the immune system’s ability to resist viral infections. Hydro-thermal therapies also confer psychological benefits and improve sleep, relieve stress, and foster interpersonal connection and connection with nature.
Hydro-thermal Therapies Can Enhance Health and Wellbeing and Help Treat and Prevent Viral Infections
- The benefits of hydrothermal therapies have been known for thousands of years and have been shown to be effective for disease prevention and health promotion [1-3].
- Hydrothermal therapies such as saunas, steam rooms, hot baths, balneotherapy, pelotherapy etc are backed by historical, epidemiological, anecdotal, clinical and randomized controlled-trial evidence that attest to their safety and efficacy.
- There is evidence to show hydro-thermal therapies such as bathing , balneotherapy , sauna bathing , massage  and healing touch  are safe and effective in the treatment and prevention of many chronic diseases .
Hydrothermal Therapies Inhibit Viral Virulence
- Enveloped viruses such as coronaviruses are most active in cool dry conditions, which are associated with increased occurrence of respiratory tract infections , including infections with SARS-CoV  and SAR-CoV-2 [20, 21].
- Warm humid environments reduce airborne droplet spread inhibit transmission of respiratory viruses and humidity of around 50% leads to slower infection and less severe illness 
- Air quality is enhanced at hot springs and thermal water inhalation is able to modulate and enhance systemic immune responses .
Hydrothermal Bathing Supports Host Resistance
- Raising body temperature through exposure to external heat is an evolutionary that has been preserved for over 600 million years and is used by fish insects, reptiles, birds, and mammals for controlling viral infections .
- There is extensive evolutionary, historical, epidemiological, physiological, psychological and clinical evidence supporting the use of heat to treat respiratory viruses as well as treat and prevent other infections and chronic diseases .
- Recent evidence shows balneotherapy and aquatic therapy improves respiratory function and helps prevent and treat respiratory diseases [27, 28].
Hydrothermal Therapies Build Community Resilience
- Bathing is essential for good health and investments in clean water initiatives that provide access to optimum bathing facilities support individual, community and global health.
- Hydrothermal treatments provide psychological benefits that are difficult to overstate.These benefits can help overcome the trauma and feelings of helplessness from forced confinement and uncertain economic and social circumstances, and include improved sleep, reduction of stress and anxiety, connection with nature and social connection [29-31].
- Supporting hydrothermal bathing as a regular lifestyle activity builds community resilience, provides medical personnel with respite, and contributes to a culture of wellness.
Common Sense Safety Principles
Heat is a powerful force and like any powerful intervention, has the potential to either harm or help. Common sense safety precautions when using heat include:
- Drink: Ensure your stay hydrated with a good quality water.
- Take care: Avoid burns or scalds near sources of heat and sudden changes in posture that could lead to dizziness or fainting;
- Know your limits: Heat tolerance varies widely between individuals and within the same individual at different times. Use your comfort level as a guide to exposure and don’t go beyond the point of being 'comfortably uncomfortable'.
- Be aware: Tune into your senses, monitor your tolerance and enjoy heat-induced forced mindfulness’. Avoid extremes of temperature when under the influence of alcohol or drugs that impair your judgement;
- Rest: Alternate exposure to hot or cold with relaxation and re-balancing periods.
Spend at least as much time resting and coming back into physiological balance as you spend in extremes of temperature.
To learn more about water therapies with Prof Marc Cohen check out our new short course Helping Your Patients Reduce Stress. This course explores the impact of stress and the scientific evidence base of some of the therapies that may be able to alleviate stress, including mindfulness, breathwork, CBT, hypnotherapy, yoga and sound therapy.
This article is a partial extract of a position paper prepared by Prof Marc Cohen called Hydro-Thermal Therapies Are Essential for Building Health, Safety and Resilience in the Age of Pandemics
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