Fahrenheit reference points became popular following the work of Anders Celsius and these fixed points were adopted by a committee of the Royal Society led by Henry Cavendish in 1776. Under this system, the Fahrenheit scale is redefined slightly so that the freezing point of water is exactly 32 °F, and the boiling point is exactly 212 °F or 180 degrees higher. It is for this reason that normal human body temperature is approximately 98° (oral temperature) on the revised scale (whereas it was 90° on Fahrenheit's multiplication of Rømer, and 96° on his original scale). The Rankine temperature scale was
Ice bath known as contrast water therapy or contrast bath therapy, in which cold water and warmer water are alternated. One method of doing this was to have two tubs––one cold (10–15 degrees Celsius) and another hot (37–40 degrees Celsius) ––and to do one minute in the cold tub followed by two minutes in a hot tub, and to repeat this procedure three times. The temperature can vary, but is usually in the range of 50–59 degrees Fahrenheit or between 12 and 15 degrees Celsius. Some athletes wear booties to keep their toes warm or rubberized coverings around their midsection while immersed.