cool down vs warm up

cool down

verb
  • To become cooler; to be reduced in temperature. 

  • To become less agitated or excited. 

  • To cause (something) to become cooler; to reduce the temperature of. 

  • To decrease in degree or intensity. 

  • To cause (someone) to become less agitated or excited. 

warm up

verb
  • To become warmer. 

  • To reach, or cause to reach, a normal operating temperature (of a car for example). 

  • To heat or reheat (e.g. food). 

  • To do gentle exercise, stretching etc., in order to prepare the body for more vigorous exercise. 

  • To make (an audience) enthusiastic or animated before a show 

  • To prepare for an activity by carrying out a practice or preparation routine. 

How often have the words cool down and warm up occurred in a corpus of books? (source: Google Ngram Viewer )