That's tenuous. I don't have anything "survival" related to report, but dangerous manly ways of passing the time and proving one's virility are always interesting.
As part of my ongoing research I joined a fencing class, but found it very hard on my thighs and knees. One cannot be fast if one is stiff, so a lot of warming up has to be done. Apparently, there were other preparations one made before fighting a duel, too.
Fasting, for instance. As there was always a danger that cold steel might penetrate the gut, duellists who knew what they were doing reduced the risk of infection by having empty stomachs, empty bladders... and so forth.
I've never seen that mentioned in a Regency Romance.