When we say “cold,” we refer to temperatures below 15°C. A typical “ice bath” ranges from 5-10°C, but our ice baths can be set between 2-40°C. The key is to make it cold enough to feel uncomfortable, creating a sensation of "I need to get out, but I can stay in safely." This feeling is unique to each person and will change as your tolerance increases.
Tips for finding your ideal "Uncomfortably Cold" :
Your threshold will vary based on factors like mental state, tiredness, workouts, or sauna sessions.
Evening cold showers are generally harder than morning ones.
Cold showers post-illness can feel more challenging than when you're healthy.
Always use common sense and listen to your body.
Remember, your perception of "uncomfortably cold" will evolve over time. Aim to find and stick to this personal threshold for the best experience.
Understanding your reason for doing it can help you stay committed and measure its effects on your mind and body.
Tool for Training: For some, cold-water immersion is simply a tool to enhance their physical training.
Inflammation Reduction: Others use it to reduce inflammation after intense exercise.
Pain Management: Many people use cold immersion to manage pain or keep symptoms in check.
Mental Health Aid: It also serves as a mental health aid for those who benefit from the norepinephrine boost it provides, helping build mental resilience.
The method you choose isn't as important as knowing your "why." This understanding will help you stay committed and see the benefits on both your mind and body.
This particular health benefit claim may have been popularised by a 2016 Dutch study where users of daily cold showers showed a reduction in self-reported sickness [27]. Since then, there have been numerous studies showing that cold exposure, typically in winter ice swimmers, increases the plasma levels of a number of different immune cells [28]. Quite simply, more immune cells in your blood is generally a good thing. A study comparing regular winter swimmers who practised more than once per week to non- habitual swimmers showed that resting concentrations of some white blood cells such as leukocytes and monocytes were higher compared to the non-habitual swimmers [29]. Another study found regular winter swimming may decrease respiratory tract infections by 40 percent [30]. These studies bolster all those anecdotal claims shared among communities of winter swimmers and cold water enthusiasts that they experience fewer colds and influenza.
The benefits around winter (ice) swimming with temperature in waters below 5°c are perhaps the most numerous and therefore the most cited, and where plasma (blood) levels have been measured objectively. The benefits of ice water exposure correlates to better immune health for reasons outlined below, and perhaps with the added of benefit of the cold exposure being undertaken in nature. Who knows the importance of the ‘nature’ aspect until detailed studies are explored - but we shouldn’t overlook it: whenever it’s safe - nature is best.
Cold thermogenesis activates brown fat immediately and boosts metabolism for hours. While not a magic weight loss solution, combining cold exposure with a healthy diet and exercise can enhance fat-burning throughout the day.
Cold Water Therapy for Body Fat:
Brown Fat Activation: Helps burn fat and improve metabolic health, especially in people with obesity or type 2 diabetes. Cold exposure increases brown fat volume and activation, turning white fat into brown fat.
Insulin Sensitivity: Improves insulin sensitivity by 43% and increases muscle glucose uptake, making it a potential therapy for diabetes.
Glucose Metabolism: Brown fat influences glucose metabolism, leading to lower HbA1c and cholesterol levels.
Cardiometabolic Health:
Lower Risk: People with detectable brown fat have a lower prevalence of cardiometabolic diseases like type 2 diabetes and coronary artery disease.
Increased Brown Fat Activation:
Metabolic Processes: Regular cold exposure (11 minutes per week) increases core metabolism and caloric burn, particularly by covering the vagus nerve.
Fat Storage: Converts white fat to brown fat, increasing overall metabolism and preparing the body for future cold exposure.
This redefines how we see cold exposure—it not only burns fat during the activity but also changes underlying metabolism. Norepinephrine released during cold exposure triggers gene expression changes, converting white fat to brown fat, showing fat cells' adaptability.
Cold exposure influences our body's natural temperature fluctuations, which are aligned with our individual circadian rhythms. Understanding these patterns can help optimize the benefits of cold-water immersion.
Body Temperature & Circadian Rhythm:
Lowest Temperature: About two hours before waking.
Natural Peak: Early to mid-afternoon.
Decline: Begins before sleep, aiding the cooling process necessary for falling asleep.
Cold Exposure Tips:
Cool Room for Sleep: A cooler environment supports deep, restful sleep.
Timing for Cold-Water Immersion:
Morning Ice Baths: Support the body's natural warming process, enhancing wakefulness and energy.
Night-Time Ice Baths: Can be counterproductive as they warm the body when it naturally wants to cool down.
Experiment with different timings to see what works best for you, aligning cold exposure with your body's natural rhythms for optimal results.
Direct cold exposure significantly impacts our metabolism, both immediately and for hours afterward. Burning brown fat is the body's most efficient way to generate warmth—think of it as a quick-firing fuel for the furnace.
It's important to note that the body continues to adapt after cold exposure, preparing to burn more brown fat stores for future instances. This ongoing adaptation enhances the body's ability to efficiently manage cold and improves overall metabolic response.
When we try to cool down using common methods, such as placing a cold, wet towel on our head or body, we may inadvertently make ourselves warmer. This happens because the body's response to prevent excessive cooling is to heat up.
Optimal Cooling Method
Cool via Glabrous Skin: Cooling the hands, feet, and cheekbones is more effective. The structure and nature of veins in these areas help dissipate heat better.
Cooling the entire body can trigger a response similar to turning on central heating. This technique is especially useful to remember for sleeping in hot weather and managing heat exhaustion.
Cold Water Immersion (CWI) has a unique ability to significantly boost dopamine, the motivation molecule. This effect sets it apart from other stressors that increase adrenaline and noradrenaline without affecting dopamine levels.
Key Points:
Dopamine Boost: CWI can increase dopamine levels by up to 230%.
Mood Elevation: This dopamine surge can significantly elevate mood for many hours post-exposure.
Mental Acuity and Focus: The increase in catecholamines (epinephrine, norepinephrine, and dopamine) sharpens mental acuity and brings focus.
Practical Applications:
Substitute for Negative Habits: According to Dr. Anna Lembke (Dopamine Nation), CWI can help individuals replace harmful habits (e.g., alcohol, drugs) with a healthier alternative that provides a similar dopamine boost.
Sustained Benefits: The benefits of CWI, including enhanced mood and mental clarity, can last for hours, making the practice habit-forming.
Overall, CWI not only improves physical well-being but also offers profound mental and emotional benefits, making it a powerful tool for personal transformation.
Cold water exposure has been shown to boost certain populations of immune cells. Here's how:
Increased Immune Cells: In healthy young men exposed to cold multiple times over six weeks, CD25 lymphocytes increased after three weeks, and CD14 monocytes after six weeks. This highlights that benefits come from repeated exposure, not occasional dips.
White Blood Cell Increase: Cold exposure increases the numbers of white blood cells, including specialized cells that can kill cancer cells. White cell counts remain elevated for two hours post-exposure.
Natural Killer Cells: These innate immune system cells also increase with cold exposure, enhancing the body's ability to fight off diseases.
These findings suggest that consistent cold exposure, like regular exercise, significantly boosts immune function.
Cold exposure, whether whole-body or localized (e.g., cold packs), effectively reduces inflammation, a key driver of aging and various diseases like arthritis.
Key Points:
Chronic Inflammation: Cold exposure helps decrease inflammation in people with inflammatory conditions and those recovering from exercise.
Arthritis Relief: Reduces inflammation and pain associated with arthritis by decreasing inflammatory signaling molecules.
Pain Management: Norepinephrine release during cold exposure alleviates pain by reducing inflammation and having an anesthetic effect.
Exercise-Related Inflammation: Cold-water immersion (CWI) post-exercise reduces muscle soreness, serum creatine kinase, and enhances recovery.
Recommendations:
Strength Training: Avoid CWI for at least 4 hours after strength training to allow necessary inflammation for muscle growth.
Endurance Training: CWI immediately post-exercise benefits recovery, reducing soreness and inflammation markers like C-reactive protein.
Aerobic Capacity: CWI boosts mitochondrial biogenesis, increasing muscle power and endurance.
CWI is beneficial for reducing inflammation and associated pain, improving muscle performance, and enhancing recovery. Regular use can lead to less muscle soreness and a greater ability to exercise consistently.