blow off steam

verb2

1. •
   To vent; to talk or take action (especially in a ranting or unrestrained way) so as to relieve stress.

   • Don't take it personally when he shouts like that. He's just blowing off steam.
   • I told her she could call me and talk any time she wanted to blow off steam.
2. •
   To do something to get rid of excess energy or worry, especially exercise or diversion.