"It's better than sex," he said, but I couldn't quite do it hard core this morn.

It's contrast baths.  Specifically, the shower version of 2 mins under cold water before the warm/hot.  The part that's so good is when the warm starts.  But it came up cuz of the not fighting the cold, not shrinking from unpleasant sensation.  How much easier it is to take when endeavoring just to let it happen.

The Brits don't just endeavor, you know.  Nor was the Shuttle merely Endeavor.