What are cold exposure’s main benefits?

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Accepted Answer

Cold exposure may have numerous benefits on the mind and body, and these benefits are currently under investigation. However, it is important to note that the way in which the stress from cold exposure interacts with various human body systems isn’t completely understood. More research is needed to determine whether certain effects are beneficial and in which populations or individuals cold exposure may be more or less appropriate.^[1]

Cold exposure has been shown to have 5 primary benefits.

Increased metabolic rate Cold exposure increases the metabolic rate^[2] through thermogenesis in the body, a process in which various metabolic pathways are activated to generate heat in an effort to preserve the core temperature.^[3] Shivering thermogenesis is one of the biggest contributors to an increased metabolic rate during cold exposure and can increase the metabolic rate in the short term by as much as 500%, given a sufficient decrease in the core temperature.^[4] However, nonshivering thermogenesis (NST) is also responsible for an increased metabolic rate as part of the body’s adaptation to regular cold exposure.^[5]

Increased cold tolerance With frequent cold exposure, the body becomes more efficient at activating thermogenic processes to maintain the core temperature. Regular cold exposure in humans increases nonshivering thermogenesis, which increases from baseline in direct proportion to cold tolerance.^[6]^[7] Additionally, studies in Norwegian fishermen — who tend to work in cold environments and are often required to immerse their hands in cold water — have suggested that cold-water finger dexterity may increase with regular cold exposure.^[8]^[9]

Increased focus and energy levels Cold exposure from cold water immersion (CWI) triggers the rapid release of catecholamines such as dopamine and norepinephrine,^[10]^[11]^[12]^[2] which are associated with increased focus, energy, and motivation levels.^[13]^[14] In a randomized controlled trial that tested the effects of cold water immersion for an hour at various temperatures, immersion in 14°C (57°F) water increased levels of the catecholamines norepinephrine and dopamine by 530% and 250%, respectively. The levels of these neurotransmitters remained elevated significantly above baseline at the 2-hour endpoint.^[2] Because catecholamines remained elevated above baseline at the 2-hour endpoint, more research is needed to determine whether they remain elevated throughout the day, which would be consistent with claims that CWI promotes a heightened mental state for several hours postexposure. Additional studies are also needed to determine whether shorter-duration CWI and extended-duration CWI may cause similar increases in catecholamine levels. However, these results are consistent with reports in another trial that the participants felt more alert, focused, and inspired after only 5 minutes of CWI.^[11]

Improved mood The positive effects of cold exposure on mood are related at least in part to its ability to increase norepinephrine levels.^[15] The participants in one trial who were exposed to CWI at 20°C (68°F) for 5 minutes experienced increased positive emotions and reported feeling less nervous and distressed, as well as more active, alert, inspired, proud, and attentive. Although the mechanisms that cold exposure affects to alter mood aren’t currently well understood, the changes in the emotional states of the participants were associated with increased connectivity between the areas of the brain that are involved with self-regulation, emotion, and attention control.^[11]

Increased resilience and mental toughness More research — including randomized controlled trials — is needed to more thoroughly test the associations between the emotional states of participants in cold water immersion studies and increased connectivity between the areas of the brain that are involved with self-regulation, emotion, and attention control. However, these associations are consistent with additional observations suggesting that cold water immersion may increase perceptions of self efficacy, resilience, and mental toughness.^[16] and supported by a larger body of evidence linking cold acclimation to a blunted sympathetic stress response.^[17]^[18]^[18]^[19]^[17]^[20]^[21] The blunting of the “fight or flight” sympathetic stress response, alongside enhanced activation of the “rest and digest” parasympathetic nervous system, may explain the tendency for cold exposure to cause increased perceptions of resilience and mental toughness. In other words, cold exposure may increase “grit” by encouraging a sense of “calm under fire”.

What are cold exposure’s main benefits?

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