Deliberate cold exposure can give many health benefits. The temperature should be cold for you to feel uncomfortable but safe, as too cold can cause shock and death. 

How long and how often should people expose to the cold? There is no definite answer at this stage but do whatever best that suits your lifestyle. 

After a cold exposure, the body heats up and when the temperature increases, it tends to wake you up, therefore, better to use cold bath or shower early in the day and not too close to bedtime. 

Most studies use ice bath or cold-water immersion but there are many waysof cold exposure in reducing effectiveness that you can use:

• Cryo chamber: expensive and not easily available
• Cold bath
• Cold shower
• Get cold: lightly dressed in cold weather

According to Dr Huberman, a solid basic and science supported protocol is to deliberately be exposed to cold temperature (cold bath or shower)for 11min /week in total to have benefits.  The water should be uncomfortably cold yet safe to stay for a few minutes.

 

Benefits of cold exposure:

Deliberate cold exposure causes a significant release in Adrenaline and noradrenaline in the brain and body. These neurochemicals make you feel alert and less agitated, increases your energy, and focus which can be applied to other mental and physical activities.

Deliberate cold exposure is a great training for the mind by forcing yourself to embrace the stress of cold exposure as a meaningful self -directed challenge (stressor). You exert control over deeper brain centre that regulates reflexive state such as control over the urge to exit the cold environment. It also enhances your sense of mind-body connection. This builds up resilience and willpower. Importantly, it is a skill that carries over to other situations allowing you to cope better and maintain a calm and clear mind when confronted with real world stressors. 

Cold exposure causes prolonged release of Dopamine. Dopamine can elevate mood, enhance focus, attention to goal directed behaviour. Even short bouts of cold exposure cause a lasting increase in dopamine and sustained elevation of mood, energy, and focus.

The body must burn calories to increase the core body temperature. The total calories burnt from the cold exposure are not that significant. However, the conversion of white fat (energy storage) to brown fat (highly metabolically active fat) can be beneficial. 

This allows cold adaptation so people can feel more comfortable in the cold. Brown fat high in mitochondria can trigger further and more sustained increase in metabolism.

The activation of brown fat may help to increase energy expenditure and may be helpful with fat loss, insulin sensitivity, lower fasting glucose in metabolic syndrome and improve dietary fatty acid handling. 

Cold exposure can be a highly effective recovery tool after high intensity exercise or endurance training.Short interval (< 5min) of cold-water immersion demonstrated positive outcomes for muscle power, perceived recovery and decreased soreness in part due to a reduction in circulating creatine kinases. Exposing body to cold reduces inflammation, swelling and sore muscles therefore many athletes use ice bath, cold shower to speed up recovery after training. 

A study of Wim Hof method participants showed an increased immune response and fewer symptoms of disease when they were injected with endotoxin. The Wim Hof method involves breathing, meditation and exposure to cold. 

You might be more susceptible to “colds” in wintertime but your immune system can adapt to the cold environment and its ability to fight off infection gets stronger. 

Studies in animals that were exposed to cold showed that those animals live longer. It could be explained by the paradoxical adaptation to the cold makes the animals stronger and become more efficient if they are exposed to environmental stresses. 

Cold exposure can slow down the aging process as it enhances complexion and rejuvenates the skin by keeping the skin tight, vibrant and radiant. 

 

Reference:

Dr Huberman: The Science and Use of Cold Exposure for Health and Performance. 

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