Cold Water Therapy is a practice that involves immersing yourself in cold water on a regular basis. This is often done after intense exercise to reduce inflammation and aid recovery.
The sudden change in skin temperature triggers the body’s fight-or-flight response and stimulates hormone production. These include cortisol, adrenaline and noradrenaline.
Whether in the form of an ice bath, cold shower or outdoor swim, immersion in cold water can help reduce the feeling of sore muscles. This is because the cooling effect of the water causes blood vessels in the affected areas to constrict, which reduces swelling and inflammation and helps flush out lactic acid buildup.
Regular cold water therapy also increases levels of the cytokine norepinephrine, which is believed to reduce the level of cortisol in the body. This decrease in circulating stress hormones is thought to reduce the feeling of muscle soreness and speed up recovery.
In a study published in the Cochrane Library, immersion in cold water was found to increase the production of the anti-inflammatory cytokine IL-6 after exercise. In addition, the plasma concentration of nitric oxide increased following short-term exposure to cold water (CWI), which was attributed to non-shivering thermogenesis and peripheral vasoconstriction.
It is recommended that those new to CWI start small and build up sessions gradually. It is important to have a warm-up and cool-down period after cold water immersion, to avoid shock to the body. A good place to start is by taking a cold shower, which is less intense than a cold bath or outdoor swimming, then building up the duration of cold immersion gradually. It is also advisable to talk to your doctor before trying this technique, particularly if you have an underlying health condition.
Stimulates the Nervous System
Cold water immersion triggers your body’s adaptive stress response, which improves its ability to handle general stress in the long run. That’s why it helps reduce anxiety and can help with PTSD.
It stimulates the release of norepinephrine, which is a feel-good hormone. It also raises the levels of beta-endorphin, which is known for its antidepressant properties. It’s not surprising that extreme athletes like Wim Hof, who holds the Guinness record for swimming under ice, are vocal proponents of cold therapy and its health benefits.
Immersing your body in cold water also causes the vagus nerve to be activated. This nerve is responsible for bringing the core body temperature back to normal. It does this by sending a message to the brain to release norepinephrine, which stimulates the sympathetic nervous system and increases your heart rate.
The sudden shock of plunging into cold water can also have other negative effects on your health, such as the ‘cold shock’ response that triggers sinus bradycardia, uncontrollable gasping, peripheral vasoconstriction and redistribution of blood flow to vital organs. However, these reactions subside with regular exposure to cold water as your body becomes accustomed to it. This enables the body to release norepinephrine more efficiently and also boosts plasma adrenocorticotropic hormone (ACTH) and cortisol levels. As a result, the body is able to reduce muscle soreness and increase circulation.
A regular daily plunge in chilly water can help your circulation by forcing your body to work harder to deliver oxygenated blood to all of your tissues. The cold exposure also stimulates your lymphatic system, which helps rid the body of toxins and waste products.
The immune and cardiovascular systems are two of the main organs that benefit from cold water immersion. When your body is exposed to cold temperatures, the hypothalamus sends hormonal signals that promote shivering to produce heat and cause constriction of blood vessels in order to prevent heat loss from the skin.
Researchers have found that individuals who regularly engage in CWI exhibit a variety of beneficial health effects, including reduced and transformed body adipose tissue, decreased insulin resistance, increased insulin sensitivity and prophylactic benefits for metabolic diseases like hypercholesterolemia. CWI also appears to be an effective stress-management tool, helping individuals to develop a stronger ability to cope with stress and anxiety.
However, it is important to note that research on the positive effects of CWI remains in its early stages, and more controlled studies are needed. Nevertheless, some of the current scientific insights include the observation that winter swimmers tend to have lower risk factors for cardiovascular disease and diabetes. Moreover, CWI appears to decrease oxidative stress in the adipose tissue and increase tolerance for stress, while it increases the number of red blood cells stored in the spleen.
Cold water immersion therapy has been proven to stimulate a cascade of hormone and neurotransmitter effects that improves the body’s health and performance. These include fat loss, reduced inflammation, a fortified immune system and balanced hormone levels. Many people find that cold exposure boosts their energy level as well. This is why a good number of athletes and wellness enthusiasts, including the infamous ‘The Iceman’ Wim Hof, take cold plunges or showers daily.
Taking a cold shower or a cold plunge is an effective way to cool off after exercise and to prepare the body for sleep. It also helps to stimulate the lymphatic system and reduce inflammation. Some research has shown that cold water immersion also stimulates the release of mood-boosting neurotransmitters. Anecdotal reports suggest that regular cold water immersion can relieve depression symptoms. This is because cold water shocks the body and triggers a surge of mood-boosting neurotransmitters, such as norepinephrine. Norepinephrine is a brain chemical that controls focus and attention, which means low norepinephrine levels can contribute to ADHD and depression.
The best time to take a cold plunge or a cold shower is 1-2 hours before you want to go to sleep. It’s important to give your body the chance to adapt to the new temperature before you get into bed. This is especially important for those who are prone to anxiety and have trouble falling asleep at night.