Taking a cold water plunge has many health benefits.
Chief among these benefits is improved lymphatic circulation. Given that your lymph fluid doesn’t have a central pump, your lymphatic system relies primarily on muscle contraction. If you don’t adequately exercise, your lymph fluid stagnates and toxins build up. Cold water immersion causes your lymph vessels to also contract and flush waste. So, cold water can serve as effective adjunct to exercise in this regard.
In addition to lymph circulation, your cardiovascular circulation is improved immensely through cold water as your blood rushes to surround your vital organs and supply every part of your body with the oxygen and nutrients it needs.
Cold water immersion also reduces the inflammation associated with exercise and mitigates the delayed onset of muscle soreness. Along with counteracting the side effects of strenuous exercise, cold water also boosts mood-enhancing neurotransmitters. Lastly, cold water promotes the conversion of white fat to healthier brown fat and thereby aids in weight management.
While completely immersing oneself in cold waters 60 degrees and below is the ideal way to produce all the desired effects, simply immersing your face in cold water is a good way to get started and also triggers the mammalian dive reflex.
The mammalian dive reflex is a physiological response to your submerging your head or simply wetting your nostrils and face while holding your breath. This reflex is shared among humans and aquatic mammals such as seals, otters and dolphins. The most noticeable effects are seen within the cardiovascular system as your heart slows by as much as 10 to 25%. The colder the water the more the response. The metabolic rate increases to compensate for the heat loss and your spleen contracts in response to lowered levels of oxygen in the blood due to the heart and brain being preferentially oxygenated. The spleen releases more red blood cells and increases the oxygen capacity of the blood.
As part of the diving response, the parasympathetic nervous system is also stimulated and vagal tone is enhanced. In today’s world where the vast majority of people are highly dominated by their sympathetic nervous systems, cold water is an excellent way to address the imbalance between sympathetic and parasympathetic.
Lastly, as a general rule, factoring in health, body mass of a person and water temperature, it takes in the order of 30 minutes for a person to become hypothermic. So, start with your wetting your face then on to cold showers then immersion and your health will thank you!
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