I'm not sure if I should put this here or the boring advice repository...

Even if you're not interested in martial arts, if you have the opportunity try to go to the first class of a session of judo or aikido and see if they'll let you take one class for free. Even if you only come the first time, the first lesson is the most instrumentally useful one -- how to fall down. Most people will never need to defend themselves in a street fight, but they're not at all unlikely to slip on a patch of ice, or misjudge a step on the stairs, or fall off a ladder, and our instincts for dealing with a fall are really counterproductive. Learning ukemi-waza may keep you out of the emergency room (one of my teachers did, in fact, fall off a ladder while cleaning his gutters, and walked away from it).