Cold temperatures

Deliberate cold exposure improves the immune system, boosts metabolism, and helps recover faster after exercising. It also increases energy, builds resilience, and enhances your mood.

Complete this habit by spending a few minutes in cold temperatures. You can use stopwatch for a cold shower/bath or an interval timer for a contrast shower/bath.

Deliberate cold exposure should last 1-5 minutes per one time and at least 11 minutes per week. Water temperature should be uncomfortably cold yet safe to stay in.

Ideally, cold exposure should be scheduled for the mornings rather than near bedtime. The cooling effect triggers your body's warming mechanisms, promoting alertness, making it more suited for the start of your day.

You might want to use the following shower protocol (it can also be used for cold baths). 

Cold shower

The cold shower is another method of deliberate cold exposure. Start this routine with warm water and slowly transition to cold water. If you feel comfortable, you can take a cold shower straight away. Going straight into cold water is the easiest and quickest method of cold water exposure. 

Cold showers train our bodies to adapt to rapidly changing environmental conditions and be resilient to stress. It boosts and strengthens our immune system and teaches us self-discipline. Exposure to cold water initiates a process in the brain that increases alertness and clarity, boosts energy levels, and makes us happy by releasing endorphins.

Instructions:

1. Begin with your regular shower routine.
2. After completing your usual routine, turn the tap to cold water.
3. An initial shock may hit you, but maintain your focus. Focus on your breathing.
4. Endure the cold for 40 seconds (after crossing this threshold, your body will relax and adjust to the cold).
5. Strive to extend this period to 1 minute.
6. Commit to this practice daily for 1-2 months to build cold resistance.
7. Once comfortable, extend the cold shower to 2-5 minutes daily to reap the full health benefits.
8. If a 40-second cold shower seems too daunting initially, begin with 10-20 seconds. If a cold shower isn't appealing, consider alternating between hot and cold water, known as a contrast shower.

Contrast shower

A contrast shower improves blood circulation, muscle recovery, deep restorative sleep, and strengthens the immune system.

Instructions:

• Perform your usual shower routine.
• Once finished, perform the following cycle:

           20-second cold water

           10-seconds hot water

• Continue for 2 - 5 min (4 - 10 cycles).

Start with 5-10 seconds of cold followed by 20 seconds of hot water. Gradually increase the time spent in cold water and reduce the time spent in hot water. It typically takes about 1-2 months for your body to acclimate and become more accepting of the cold water.

Enhance effect

To maximize the metabolic benefits of cold exposure, resist the urge to warm yourself immediately after emerging from cold water. Avoid wrapping your arms around yourself, huddling, or toweling off. Allow your body to naturally initiate shivering, which triggers the release of succinate from your muscles, thereby stimulating thermogenesis in brown fat.

It is worth noting that when water in a cold bath isn’t cold enough, move your limbs to increase the potency of a cold stimulus. Moving your limbs will prevent the thermal layer from surrounding your body and thus “insulate” you from the cold. 

Workout results

Research has indicated that immersion in cold water following high-intensity or endurance exercise can promote muscle recovery, enhance muscle power, and alleviate muscle soreness.  Cold exposure should be performed 6 to 8 or more hours after the training or before a workout to avoid adverse effects like limiting some of the gains in hypertrophy.

Safety

Listening to your body when introducing it to cold exposure is essential. Begin with warmer water, gradually adjust the temperature, and allow your body sufficient time to adapt. Do not perform any deliberate hyperventilation before or during water immersion. Always feel what your body needs, know your limits, and stay safe.

Benefits of cold

Studies conducted on various experimental animals have yielded encouraging findings in cold therapy. Both cold water and air exposure enhanced recovery from traumatic injuries, boosted metabolic activity, and lowered cancer incidence rates in these subjects. In humans, cold therapy has been linked to reduced tension and fatigue, improved memory and mood, and decreased rates of infection and depression.

One study revealed that consistent prenatal temperature exposure below the cold threshold (5.0°C) was associated with longer telomeres.

Metabolism and brown fat 

Cold exposure has been found to stimulate the production of brown fat. Activated by cold, brown fat accelerates metabolism, burns white fat, and generates more energy. As we age, the production of brown fat diminishes, and cold therapy may help delay the aging process. It was scientifically proven that lowering body temperature during sleep at night (e.g., using a thinner blanket) also fosters the production of brown fat.

Enhanced mood

Even short exposure to cold prolongs the release of dopamine (a hormone that positively affects mood, attention, focus, and motivation), resulting in an elevated mood.

Increased energy and focus

Deliberate cold exposure also releases epinephrine (aka adrenaline) and norepinephrine (aka noradrenaline). Due to cold temperatures, these neurochemicals stay elevated for some time, thus increasing energy and focus.

Resilience & grit

Exposure to cold increases levels of norepinephrine and epinephrine in our brain and body, causing stress. The exact process happens every time we experience tension or have to act under unfavorable conditions. Thus, by willingly putting yourself under stressful situations in a safe and controlled environment (e.g., embracing cold therapy), you simultaneously train yourself to deal with real-world stressors with a calm and focused mind.

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