Preparing for Polar Plunges, Health Concerns

From Redding to Rancho Cordova, Cayucos to San Pedro, thrill and chill-seekers are polar-plunging into the new year. Babes in parents' arms to centenarians all encounter cold shock, a condition that occurs when the body is immersed in icy waters. Research on the human body's physiological and psychological response to adverse environments found that it takes as few as five immersions in icy water for the body to develop a tolerance that can reduce the risk of cold-shock response by half.

Beneficial to many, cold water may:

Provide an adrenaline rush as stress hormones are released by the body
Decrease uric acid levels
Increase gluthathione, an antioxidant that keeps all other antioxidants performing at optimal levels
Lower blood pressure
Clear blocked arteries
Improve the immune system
Relieve muscle pain
Stimulate weight loss

But in people who are at a high risk for heart disease cold water may:

Cause blood vessels in the heart to constrict, leading to angina chest pains or a heart attack
Put strain on the heart as blood vessels on the outer part of your body constrict to try to retain heat
Cause hyperventilation and temporary paralysis or weakness

What's the best way to take the plunge?

Prime your body for the event several days before by gradually lowering the temperature of your shower.
Take a slow walk into the water to acclimate the body to the cold.
Ease out of the water just as you eased in.
If you've been in cold water for up to 30 minutes, soak 10 to 15 minutes in a hot bath -- but no more than that.