When I started, it was 2.5 minutes of horrible feelings, then next 2.5 minutes were kinda Okay. Nowadays the adaptation takes like 3 seconds, then I just coast under cold water. And I sometimes take a cold shower at 3am and go to sleep right after. Body adapts.

But I haven't really seen it helping to get rid of belly fat; it helps sore muscles recovery after/during workout significantly though. For belly fat I still need to do all the aerobic exercises and proper diet until 6-pack shows up.