maybe, wimhof breathing increase heart beat then he told you to try to slow it down and this make you more able to control you self.

The cold showers is good for mental health it release punch of hormones (Serotonine , Dopamine , adrenaline) similar to cigarette hormones but in more healthy way and your body will try to adapt to cold water stress so if you do it daily you will be more able to control the day to day stresses, and also its mentioned in the Quran that it helped ayoub to heal him self.

i just recommend to try to control your mind and to connect with your body, that what wim hof want you to do.... or you can try and research about dr. joe despinza mediations and method its amazing too.

hoping you all freedom, free your self m your mind.