by Ben Greenfield
Benefits from frequent cold exposure done the right way, such as:
Lowering body fat
Increasing hormone levels
Improving sexual performance and fertility
Lowering blood sugar
Cutting food cravings
Improving adrenal function
Fixing thyroid issues
Enhancing immune function
Improving deep sleep quality
Increasing pain tolerance
Reducing inflammation
So why does cold exposure achieve some of these benefits?
Adinopectin Activation
Adinopectin is a hormone released during cold exposure that breaks down fat and shuttles glucose into muscles (which can lower blood sugar). This not only has an anabolic, muscle repair effect, but can also enhance recovery. Interestingly, low adiponectin levels have been associated with obesity, diabetes, and cardiovascular disease.
Adinopectin chalks one point up for getting exposed to some cold post-workout (more on that later).
Enhanced Immune System
Cold therapy has been proven to enhance the immune system, primarily by increase levels of immune system cells that help fight disease and infection.
Specifically, cold exposure – likely due to it's ability to stimulate norepinephrine release – can induce leukocytosis and granulocytosis, an increase in natural killer cell count and activity, and a rise in circulating levels of interleukin-6, all of which can massively improve your immune system integrity.
Increased Cell Longevity
Cold exposure has an effect on cellular longevity by similar as caloric restriction and intermittent fasting. Basically, you can think of it as a combination of simultaneously increasing your cell's hardiness and health.
Higher Metabolism & Lower Blood Sugar
Cold exposure can cause blood glucose to be burned rapidly as fuel to assist in heating the body or stored in muscles to enhance recovery or performance – before that blood sugar can potentially be converted to fat via the liver.
Should You Ice After A Workout?
1. Ice does not completely reduce inflammation based swelling. But ice can preventexcessiveswelling from occurring for along period of timeafter the initial injury occurs. While some swelling certainly does important healing components such as white blood cells and other chemicals involved in the healing process to migrate into damaged tissues through increased vascular permeability, and also physically protects an injured area through decreasing it’s potential range of motion,there is no physiological reason to allow swelling to freely progress for hours or days after an injury occurs
In fact, prevention of excessive swelling is important because fluid that has escaped into the tissues from excessive swelling can create a low oxygen (hypoxic) environment that can lead to additional tissue damage and delay healing. In addition, swelling can cause distention in joint capsules and other tissues, and excitation of nervous system components called mechanoreceptors –which can increase pain. Ice simply reduces this effect by causing vasoconstriction (shrinks blood vessels) around the vasculature surrounding an injury.
2. The cold temperature of ice can slow down nerve conduction velocity and shut down the activation of your muscle spindles, making it a highly effective pain reliever and muscle relaxant. If a muscle is in less pain and is more relaxed, then mobilization and movement become a reality, and a return to functional training status can occur much more quickly,which can limit muscle atrophy or loss of fitness.
4. Finally, ice causes vasoconstriction, or shrinking of blood vessels. But unless you’re in extreme conditions where you must shuttle blood to your brain and vital organs to survive,your body will avoid tissue death by not allowing the body part you’re icing to cool excessively. Through a process called “reactive vasodilation” (also known as the Hunting reflex or Lewis reflex), your vessels, while being exposed to cold, create a negative pressure in the capillary system, which causes a pumping of inflammatory and metabolic byproducts out of an injured area, while allowing additional healing components such as macrophages and white blood cells to mobilize into the area. When combined with pressure and elevation, this “pumping” action of ice can be an extremely effective rehabilitation tool (and you can observe this in nature by simply jumping into a cold lake for about 20 minutes and watching your skin slowly turn red as reactive vasodilation occurs).