We have an early spring here, outside temp is about 5 deg C, and cold cold water is 16 deg C. It is already better than in January when we had outside temp in -5 to -10 deg range. Maybe I've got used to it but right know 5min is kinda easy, 2 months ago 30s was shocking expierenceI thought I was getting tougher by plunging into a "cold" shower and staying there for 10 minutes but it felt way too comfortable and I was wondering if my water wasn't cold enough. I put a thermometer in a jug & filled it with "cold" water and it was only 21 deg C, so I think I've been having myself on there. Maybe by the time winter gets here the cold water will actually be cold.
@Antti Maybe you want to tryThis question asked by someone suffering from sleep apnea.