As Cold as Ice: How cold training can help you live a stronger and healthier life.
Coen Fredriks is a curious human, interested in tech and life. You can find him on LinkedIn.
Eleven years ago, I stood at the edge of my first cold challenge. A Facebook post from a friend about a cold water training workshop caught my eye, and something about it stirred a quiet curiosity. At the time, I avoided cold water at all costs—I lived near (5km) the North Sea in Haarlem but rarely swam, crafting excuses to keep my distance, I hated the cold. But this workshop felt like an invitation to confront something deeper, something I couldn’t yet articulate. But that day would become a turning point in my life.
What I learned at the workshop transformed not only how I viewed the cold but also it was the start of some strong life lessons. Cold exposure has reshaped my body, mind, and ability to face life’s challenges. After the workshop, I started a daily cold training. A daily course with breath exercises, yoga, and cold water experiences.
Just weeks into my cold training journey, I noticed subtle physical shifts. My body seemed to wake up in a new way. The cold morning shower switches my body on. I felt literally a little warmer and more active in the mornings, and my energy became steady the whole day. Because the cold heats your body from the inside out. Something which Wim Hof is calling inner fire. At the workshop (in 2013), Wim Hof had mentioned brown adipose tissue (BAT, a type of body fat that regulates your body temperature in cold conditions), explaining how repeated cold exposure turns this heat-generating fat into an active calorie-burning system. Though I couldn’t see the process, I could feel it. Over time, I learned that these metabolic changes weren’t just about surviving the cold. They were about equipping my body to thrive in response to it. My first 30-second cold showers had set something larger in motion: A rewiring of my physiology that made me more efficient, more alert, and more resilient over time. It is a stress training everybody should consider.
When I stepped into my first ice bath, I felt the blood drain from my fingers and toes almost immediately, a stark reminder of my body’s ancient survival mechanisms at work. Back then, I didn’t fully understand how this process—vasoconstriction followed by vasodilation—would improve my circulation long-term. But over years of daily cold showers and regular immersions, I started noticing changes: Warm feet even in winter, quicker recovery from intense workouts, and an overall sense of vitality I hadn’t felt before. These weren’t just abstract benefits—they were tangible proof that my circulatory system had evolved to handle cold exposure with precision. What began as a shock became, over time, a symphony of function and recovery.
‘But the cold taught me something invaluable: I could face that surge of adrenaline and stay present.’
In 2019, I faced one of the most harrowing periods of my life: a business collapse that spiraled into lawsuits and crushing stress. Every morning, I turned to the cold for clarity. As I stepped into the shower or submerged in the ice, I could feel my body’s fight-or-flight response kick in, much like the stress I experienced in courtrooms and negotiation tables.
But the cold taught me something invaluable: I could face that surge of adrenaline and stay present. This training became my lifeline—an anchor in chaos. With each controlled exposure to discomfort, I sharpened a mental edge, learning to regulate my stress response and tackle challenges with focus instead of panic. The cold taught me resilience—my greatest takeaway from those grueling months.
Becoming a father shortly after starting my cold training journey gave me a newfound appreciation for its mental health benefits. I often felt overwhelmed between sleepless nights and the pressures of parenthood.
But my daily cold showers became a reset button—moments where anxiety lifted and calm returned. It wasn’t just the endorphin rush; it was the sense of agency, the realization that I could choose to face discomfort and come out stronger. Over time, this practice gave me new confidence in navigating not just cold water but the complicated waves of life itself.
Cold training works by harnessing the body’s natural adaptive responses to stress. At the heart of these changes lies the activation of brown adipose tissue (BAT), a specialized type of fat tissue that burns calories to generate heat. Unlike white fat, which stores energy, BAT is metabolically active and plays a role in thermogenesis—the body’s ability to produce heat in response to cold. Research shows that repeated cold exposure increases BAT activity and volume, leading to better fat utilization and insulin sensitivity. Over time, this adaptation contributes to improved metabolic health and energy efficiency.
Additionally, cold exposure triggers a cascade of hormonal and biochemical responses. Adrenaline and noradrenaline surge immediately as the body reacts to the cold shock, sharpening focus and mobilizing energy. Cortisol, another stress hormone, rises briefly but normalizes quickly with regular practice. These acute stress responses activate the body’s antioxidant defenses and improve resilience through a process called hormesis—a concept where low doses of stress stimulate beneficial adaptations. Blood circulation also undergoes profound changes. During cold exposure, vasoconstriction (narrowing of blood vessels) helps preserve core temperature, followed by vasodilation (widening of vessels) upon rewarming. This cycle improves vascular elasticity and cardiovascular health over time.
Perhaps most fascinating is recent research on cold training’s immunological effects. Studies, including the groundbreaking 2014 endotoxin study on Wim Hof practitioners, demonstrate the ability to voluntarily influence inflammatory markers through breathing techniques and cold exposure. Participants trained in the method showed milder flu-like symptoms and reduced inflammatory responses when exposed to bacterial endotoxins, highlighting cold training’s potential for managing inflammation and autoimmune conditions. These findings expand our understanding of the mind’s ability to communicate with and influence the immune system, challenging previous assumptions about what’s under conscious control.
Eleven years ago, the concept of cold training felt as distant as the Arctic waters themselves. It was something for others, not for someone like me who craved comfort and avoided the unknown. But now, looking back, I see how those first steps into discomfort changed the trajectory of my life. The Wim Hof method wasn’t just a series of practices; it was a gateway to resilience, clarity, and control. Through science and experience, I discovered that the cold wasn’t an adversary. It was an ally, showing me how to thrive under pressure.
A new chapter in my cold training journey began in 2022 when I participated in the first Hyrox event in the Netherlands, an intense endurance competition that pushed me to my physical limits for one-and-a-half hours. As a first-timer in such a high-intensity competition, I quickly realized the pivotal role cold training could play in my preparation and recovery. Cold water immersion became essential for restoring my body faster after grueling training sessions, while the controlled breathing I practiced during cold exposure helped me regulate my breathing during intense bursts of effort. In 2024, I returned to Hyrox more prepared and am currently training for another edition this May in 2025.
Maybe the most valuable lesson is that cold showering can teach you how to be present in the moment. When your head touches the cold water, there is nothing you can think of, you can not speak. You only can experience the cold water, the cycle of your breath you are in that moment, you are fully present.
An intriguing insight from my training involves using a Whoop strap during my cold showers. The device consistently registers a "high stress level"—the highest you can achieve in Whoop. Highlighting that even after 10 years, cold exposure still triggers an acute stress response. It’s a reminder that the cold never truly becomes ‘normal’; instead, it remains a powerful tool for invoking resilience, one that continues to demand presence and focus with each exposure.
Practical Advice: Starting Your Cold Training Journey
For anyone curious about starting their own cold training journey, the key is gradual adaptation. Diving straight into an ice bath may be tempting, but a controlled, step-by-step approach is safer and more sustainable.
Start with Cold Showers: Begin by finishing your regular warm showers with 15-30 seconds of cold water. Focus on steady breathing and avoid tensing your body. Gradually increase the cold-water duration over days or weeks as your tolerance improves up to around 120 seconds a day.
Use Breathing Techniques: Incorporate breathing exercises similar to those taught in the Wim Hof Method to help regulate your nervous system. Deep, rhythmic breaths during exposure can mitigate the shock and bring a sense of calm.
Practice Consistency: Make cold exposure a daily habit. Even short, consistent exposure is more effective than infrequent, intense sessions. Over time, your body will adapt, and the benefits will compound.
Listen to Your Body: Pay attention to any warning signs like persistent shivering, dizziness, or numbness. Cold training should challenge but not harm you. Always respect your limits.
Progress to Ice Baths: Once you’re comfortable with cold showers, you can explore ice baths or cold plunges. Aim for 1-2 minutes initially, gradually increasing the duration as you build tolerance.
Gear for Safety: If you’re training outdoors in cold weather, ensure you have adequate preparation. Warm clothes, dry towels, and a safe environment are crucial to avoid hypothermia.
Track Your Progress: Consider using tools like the Whoop strap to monitor your body’s responses to cold exposure. This can provide insights into how stress affects your system and help you optimize your practice.
These small, incremental steps will allow you to experience the transformative power of cold training safely. Remember, the goal isn’t just to endure the cold but to learn from it—using each exposure as a moment to build resilience, focus, and control.
Cold training has become more than a practice. It’s a metaphor for life itself. Stepping into discomfort, controlling your response, and emerging stronger on the other side. It’s a cycle I’ve lived through cold showers, ice baths, and even life’s toughest challenges. For anyone curious about what lies beyond the limits of comfort, the cold has lessons waiting. All it takes is the courage to begin; 11 years ago, curiosity made me decide to start with this. Years later, it is part of my daily routine, and I love it.