"Go for it! When the cold water hits the surface of your skin (which has four layers) all the blood from way deep inside your body rushes to the surface in self-defense, vastly improving your circulation on the spot. This is called Hydrotherapy. It strengthens your entire nervous system. People pay huge sums of money for what is now called "Hydrothermal therapy" when in reality all you need is cold water!
But first, before you get wet, massage your body all over with a little oil. Oil is more easily absorbed by the skin when it is mixed with water–and you won’t be greasy afterwards. Almond oil is highly recommended since the almond contains so many minerals, and it nourishes the body through the pores of the skin.
Go in and out of the water four times, constantly massaging your body until the water no longer feels cold. Be sure not to miss the area under your arms, which is where the parasympathetic and sympathetic nervous systems meet. You can even stand on one foot and massage the top of it with the other foot. Women, be sure to massage your breasts."
Above Information From the Book:
The Flow of Eternal Power by Shakti Parwha Kaur Khalsa
Your first victory of the day! You will probably become very holy the moment the cold water hits your body, because it is likely you will shout, "Oh my God!" You might try exclaiming "Wahe Guru" ("Wow, God is Great!") or "Ang Sang Wahe Guru" ("God lives in every limb of my being.") Remembering God is always a blessing.
Dry off briskly with a rough towel till the body really shines; put on loose, comfortable exercise clothing, and you’re ready to do your sadhana, your personal daily spiritual practice. God bless you, you’re bound to have a wonderful day!
Exceptions for women: Don’t take cold showers during your monthly period and No cold showers after the seventh month of pregnancy; take lukewarm, body temperature showers instead.
The Flow of Eternal Power by Shakti Parwha Kaur Khalsa "When we do ice-cold water massage, not only do we open up the capillaries, but when they return to normal, that blood goes back to the organs."