Why I Love Cold Water Immersion

One of my favourite activities at my fitness club is cold water immersion. I willingly submerge my body into a pool of 12-degree water, embracing the cold that offers both a mental and physical reboot.

Cold water immersion (CWI), a practice I’ve woven into the fabric of my daily routine, isn’t merely a challenging physical activity but an avenue to tap into unseen mental and physiological realms.

The Science Behind Cold Water Immersion

The science on CWI has come a long way in recent years, though it’s still not the holy grail that personalities like Wim Hof make it sound like. In my opinion, it’s just one more activity that can help maintain a state of well-being. That said, we now have some solid research to draw from.

Here’s what science tells us about cold water immersion:

Physical Effects on the Body: When your body hits the cold, it triggers vasoconstriction, diverting blood to vital organs and engaging the metabolic systems to preserve warmth. It’s a natural, physiological response that bolsters circulatory efficiency. Cold exposure also activates brown adipose tissue (brown fat), which burns energy to generate heat — a process that continues after you exit the water as your body rewarms naturally.
Dopamine and Norepinephrine: This is where the research is most compelling. A study by Sramek et al. found that cold water immersion at 14°C causes up to a 2.5-fold increase in dopamine and a 5-fold increase in norepinephrine. Unlike stimulants, these increases are gradual and sustained rather than a spike-and-crash. This is the mechanism behind the alertness, mood boost, and mental clarity that regular practitioners report — and it’s one of the main reasons I keep coming back to the cold pool.
Stress Resilience: A 2025 systematic review published in PLOS ONE found a significant reduction in perceived stress 12 hours after CWI. Interestingly, the benefit doesn’t show up immediately — it kicks in later. Regular cold exposure appears to train your autonomic nervous system to handle stress more effectively, which is something I’ve noticed in my own experience.
Immune System: The evidence here is less conclusive. Meta-analyses have found no significant acute changes in immune markers. However, one large study of over 3,000 participants (Buijze et al.) found a 29% reduction in sick days among regular cold shower users. Suggestive, but far from proven.

Duration and Immersion Recommendations

How Long Should You Stay In? The recommended time for cold water immersion can vary depending on experience and tolerance levels. For beginners, starting with 1-2 minutes is ideal. As you become more comfortable, you can gradually extend your time to around 5-10 minutes. However, it’s important not to push beyond your limits. Research suggests that 11-15 minutes per week, split across multiple sessions, can be sufficient to gain the desired physiological benefits without overexposure to cold stress.

Which Parts of the Body to Submerge? To achieve the full benefits of CWI, it is generally recommended to submerge as much of the body as possible, ideally up to the neck. This ensures the core, which houses the majority of vital organs, experiences the effects of the cold. However, even partial immersion (such as submerging just the legs or arms) can provide benefits for circulation and inflammation reduction. Hands and feet are often the most sensitive, so you might find it easier to keep them out initially until you build tolerance.

Submerging the head in cold water immersion can have additional effects, both positive and negative. On the positive side, dunking your head can activate the mammalian dive reflex, which helps lower heart rate and conserve oxygen, potentially enhancing relaxation. However, sudden head immersion also carries risks, particularly for individuals who are not used to it. The rapid cooling of the head can lead to a sudden spike in blood pressure or even cause lightheadedness or fainting.

If you decide to submerge your head, it’s best to do so gradually. Start by wetting your face and the back of your neck before slowly dunking your head. This can help your body adjust more comfortably and safely to the extreme temperature. As always, listen to your body and don’t push beyond what feels safe.

It’s also quite common for men to experience discomfort in the groin area, particularly in the testicles. This discomfort happens because the body instinctively attempts to protect reproductive organs from the extreme cold by drawing them closer to the body, leading to a tightening sensation and sometimes pain. If the discomfort is too much, wearing neoprene shorts can help provide some insulation while still gaining the overall benefits of cold exposure.

My Personal Routine

Preparation: Before I enter the pool, I ensure mental alignment with the impending cold and adhere to safety, ensuring I’m well-rested and not alone during the process.
Execution: Slow and deliberate, I enter the water, focusing on maintaining controlled, steady breathing to counter the initial shock and gradually immerse my entire body.
Post-Immersion Process: After getting out, I let my body rewarm naturally rather than jumping into a hot shower. This is important — the shivering and natural rewarming process is when brown fat activation and metabolic benefits actually occur (this is sometimes called the Soberg principle: “end on cold”). I then focus on replenishing with nutritious food and taking a moment to reflect on the experience.

Timing matters. When incorporating CWI into a fitness routine, it’s crucial to be mindful of when to take the plunge. I practice CWI after my padel matches as an aid to recovery and lower inflammation, but I avoid it after weight lifting sessions. This isn’t just a hunch — a 2024 meta-analysis by Pinero et al., published in the European Journal of Sport Science, confirmed that cold water immersion significantly attenuates muscle hypertrophy compared to resistance training alone. The mechanisms are well-established: cold suppresses mTORC1 signaling, satellite cell activation, and muscle protein synthesis — all the pathways that drive muscle growth.

The key distinction is that feeling less sore is not the same as recovering better. Cold suppresses the inflammatory response your body actually needs to adapt and grow from strength training. Interestingly, strength gains are less affected than hypertrophy — you can still get stronger, but you’ll build less muscle.

If your goal is to enhance muscle gains, avoid immersing within at least 4-6 hours of lifting sessions. The anabolic window where these growth signals are elevated extends for hours post-training, and applying cold during this window is where the blunting occurs. Instead, schedule CWI on rest days, after cardiovascular activities, or after sport sessions like padel where you’re not chasing hypertrophy. For general stress relief and the dopamine benefits, early mornings or after work are ideal times that won’t conflict with muscle recovery.

Benefits and Challenges

This daily plunge has fortified not just my physical being but also my mental resilience, offering a consistent space to practice surrender and grit simultaneously.

It was never easy. To this day, cold showers are too difficult for me, but I found that the plunge is something I can do consistently. Having said that, the initial fear and physical discomfort were barriers that required persistent and mindful efforts to overcome. If you feel the same, know that it’s absolutely normal. If you never manage to get accustomed to cold water immersion, that’s also OK; it’s not essential to your well-being—just find something else that works for you.

Compression Sleeves: A Complementary Recovery Tool

If you’re looking for a recovery tool that helps without any risk of blunting your training adaptations, compression sleeves are worth considering. A 2025 meta-analysis of 28 studies found that compression garments provide a small but significant benefit to strength and power recovery, along with a moderate reduction in perceived soreness. The benefits are strongest for the lower body, likely because of the greater muscle mass and longer venous return distance in the legs.

The important difference between compression and cold is how they work. Compression reduces swelling mechanically by improving venous return — it doesn’t interfere with the underlying inflammatory and repair processes your muscles need to adapt. Studies show that compression doesn’t change creatine kinase or inflammatory markers, meaning the adaptation process proceeds normally while you simply feel less sore and perform better in your next session.

For someone like me who does both strength training and plays padel regularly, the practical approach is straightforward: compression sleeves (especially for calves and knees) can be worn for hours after any type of session without worry, while CWI should be reserved for rest days or after sport sessions where muscle growth isn’t the goal. It’s not one or the other — they serve different purposes and work well together as part of a broader recovery strategy.

Conclusion

My journey with CWI has been really interesting. I have gained a deep appreciation for the body’s capacity to adapt and find calm in chaos. It has helped me build up the ability to prepare myself for adverse conditions, rather than constantly be in a responsive mode, changing my moods and level of motivation as a reaction to outside factors. While my experiences are personal and subjective, the underlying theme of embarking on a journey of self-discovery through pushing physical and mental boundaries is universally relevant.

Ultimately, cold water immersion is about more than just braving the cold—it’s a tool for resilience, mental clarity, and adaptation. If you’re curious, start small, and listen to your body as you progress. It’s not about following a fad but finding what adds value to your well-being.