Ice baths have gained remarkable traction in recent years, transitioning from a niche practice among elite athletes to a mainstream wellness trend. With numerous studios now offering ice baths or “contrast therapy” – a combination of sauna and cold immersion – the practice has captivated the attention of health enthusiasts and influencers alike. However, while the trend is booming, it is crucial to understand the potential health risks involved.
Historically, cold water immersion is not a modern concept. The “frigidarium,” a room featuring a cold plunge pool, was a staple in Roman bathhouses. For decades, athletes have utilized cold water immersion techniques to aid recovery. Yet, with the emergence of commercial cold plunge centers, more individuals are now seeking the experience recreationally, even constructing their own ice baths at home. According to market analysis, the global cold plunge tub market was valued at approximately US$338 million in 2024 and is projected to grow to nearly US$483 million by 2033.
The allure of ice baths is often amplified by social media, where influencers promote the practice as a path to enhanced mental health, increased serotonin and testosterone levels, and improved metabolism. Despite these claims, scientific backing remains limited. While some studies indicate that cold water immersion can alleviate muscle soreness, the effects are typically modest and temporary. Additionally, claims surrounding mental health benefits and weight loss lack robust evidence, often resting on anecdotal accounts rather than verified research.
Understanding the Risks
At commercial establishments, users can typically access ice baths without much oversight. Temperatures in these baths often range from 3°C to 15°C. While some enthusiasts add ice to their home setups, the lack of active supervision raises significant concerns regarding safety and individual limits.
Cold water immersion triggers a strong physiological response. When submerged in temperatures below 15°C, individuals can experience cold shock, characterized by rapid and uncontrollable breathing, increased heart rate, and elevated blood pressure. Prolonged exposure can result in hypothermia, where the body’s core temperature drops to dangerous levels. Symptoms such as shivering, confusion, or fainting can indicate the onset of this serious condition.
Research dating back to 1969 demonstrated that even experienced swimmers can struggle in cold water. Participants immersed in 4.7°C water reported respiratory distress and had to cease swimming within minutes, well before any measurable decrease in core body temperature. The phenomenon known as “afterdrop” can further complicate recovery, as core temperature may continue to decline even after exiting the water.
An incident reported by one of the authors, Sam Cornell, underscores the potential dangers of ice baths. While providing first aid at a facility in Sydney, Cornell witnessed a young man collapse after ten minutes in an ice bath, exhibiting signs of cold shock.
Furthermore, prolonged exposure to cold water can lead to long-term damage to nerves and blood vessels in extremities, a condition known as non-freezing cold injury. Symptoms can include persistent numbness and sensitivity to cold, lasting for years.
Guidelines for Safe Ice Bath Practices
While the trend of ice bathing is gaining momentum, caution is essential. For those considering the experience, the following recommendations can help mitigate risks:
1. Consult a healthcare professional: Before attempting cold water immersion, individuals should discuss any existing health issues, especially those related to the heart, stroke, or respiratory problems.
2. Recognize personal limits: Physical fitness does not guarantee immunity to cold shock; understanding personal tolerance is vital.
3. Start gradually: Transitioning from warm to cold showers can help acclimatize the body before full immersion.
4. Never immerse alone: Always have a companion present, especially for first-time users, to ensure safety.
5. Limit duration and monitor temperature: Sessions should ideally last between 3–5 minutes, as risks can arise even after exiting the bath.
6. Be alert to warning signs: Symptoms like shivering, numbness, and confusion should not be dismissed as part of the experience; they may indicate the onset of hypothermia.
As the ice bath trend continues to attract attention, individuals should approach the practice with a balanced understanding of both its appeal and its risks. By adhering to safety guidelines and maintaining awareness of personal health, enthusiasts can enjoy the benefits of cold water immersion while minimizing potential dangers.
