Tempering is the act of exposing the body to regularly scheduled sudden onslaughts of cold water. Traditionally this is done through by, essentially, polar bearing or cutting a hole in the ice of a lake and jumping in or running into the cold ocean. If these traditional methods are not available, tempering can be done dumping three, five gallon buckets of ice cold water on yourself, or around 57 liters/litres. Tempering should be preceded by joint/mobility stretching or training. Proper tempering is done once or twice a day, without missing a single session. Tempering should never be followed by a hot/warm shower. It is recommended that a person tempers first thing in the morning and, if a second time, twelve hours later.

Tempering has been studied to have many positive effects. The body responds to tempering by raising the internal temperature, quickly and momentarily, to almost 42.2 degrees Celsius or 108 degrees Fahrenheit. The other positive affects have been found, but not limited to, increased immunity, sharper muscle tone, heightened metabolism, and stimulated central nervous system.

The tempering tradition is supported by Pavel Tsatsouline in his systems of power training. His method focuses on ”winter swimming” as opposed to using the buckets. The Russian System Guidebook by Vladimir Vasilev also promotes tempering citing its use in training Russian Special Forces.