This is just a weird flex on various different levels.
#1 Joe Rogan owns an Icebath in his backyard (Very expensive and hard to keep water super cold in Austin Heat)
#2 Joe Rogan is in the ice bath for 20 minutes (Kinda Impressive)
#3 He is doing extreme breathing exercises that are hilarious
Joe Rogan is a very, very successful comedian and podcaster but I really wonder if when he posted this if he realized this was unintentionally hilarious rather than something cool to get respect from his Navy Seal buddies.
Also, Joe Rogan has insane steroid nipples. Didn't need to see that. This was most likely the completion of a Fire and Ice combo in follow-up to his fire sauna picture.