1) I'd picked up a small groin strain. (That's the language of groin strains, by the way. It's always "pick up" - there's less a sense of unusual tearing injury and more one of everyday peskiness. "Coming to the pub, Barry?" "Nah, can't, mate. I've got to go to Tesco's to pick up the missus and a groin strain.")
2) I do aikido (just think "jujitsu for liberals").
2) is fine; 1) you can live with; 2) and 1) together spell this word: "Arrrgh!" There are some fearful noises in life - dentists' drills, say, or the theme music that means My Family is about to start - but there's little to beat being upside-down in mid-air, doing a somersaulting break-fall, and your head suddenly filling with the sound of your own groin ripping apart.
An evening at A&E, packing my crotch with ice, and several days of agony? Pshaw - 'tis nothing. Delicate weeks where having sex with my girlfriend is a dangerous proposition? Meh - having sex with my girlfriend has always been like that: she's German. What's made me anxious is it's been months now, and it's not right yet. Simple, workaday stuff is mostly fine, but it's still there: wobbly, weak and winceful. My girlfriend's sister can feel rain approaching with her episiotomy scar (she's a hit at parties). Will this be that kind of thing? Will I, in 10 years, be holding my groin, muttering, "There's a frost coming"? Possibly, the way TV's headed, for Channel 5 weather?
My groin is a worry.