I follow a lot of health, fitness and wellbeing accounts on Instagram and everyone seems to be caught up in this trend. Basically, you fill a bath with ice water, plunge yourself in for 5 minutes, then jump out looking energised and renewed. Some people are even lowering themselves into frozen lakes. You also need to film yourself doing this and tag Wim Hof every single time.
I actually started browsing for a foldable ice bath on Amazon before coming to my senses and remembering it takes me half hour to get in a heated pool let alone a bucket of ice.