I do open water swimming through the winter in Melbourne with no wetsuit. Mid-winter it gets to about 8-9C, and I stay in about 20-30 minutes. There's definitel

I do open water swimming through the winter in Melbourne with no wetsuit. Mid-winter it gets to about 8-9C, and I stay in about 20-30 minutes. There's definitely a mental health benefit, probably largely from doing the thing that seems difficult to do, but once you're started it fine. I also notice that at night, after such a swim, I run _really_ hot. Like, don't need a doona, even in the middle of winter in an un-heated and un-insulated house. Overall, I like it, but it's taken years of slow acclimation to get there.