Hypo-Active Athlete

In December I was having a conversation.  We hadn't met before and we were making small talk.  The chat turned to leisure pursuits, and I mentioned that I enjoyed swimming in the sea.  Then I sat back, expecting to be revered as a sort of viking crossed with a killer whale.  "Oh, wild swimming?" She asked. "That's cool - my gran does that in Brighton" You could actually hear the peg or two that I had been set down tinkling to the floor.  Peggily. I've had much the same experience making public my illness.  What seemed huge, monstrous and, dare I say it, heroically overcome thus far, has not exactly ignited the fires of those around me.  I've run the gamut of "My auntie/mum/gran has that" and even "yeah, my cat had it but it died soon after". So I started to draft questions.  Mostly but not exclusively unrelated to cats. Firstly, how common is this?  I don't know anything about it other than a doctor called me up after 18.00 on

I've got to say it came as rather a surprise.  I assumed that stuff hurting was just what happened as you got older.  Since my mid-teens I've been doing sports that have been a bit hard on the old body, and then from University onwards, more so. The roll call of sports just seemed destined for old age carnage: whitewater kayaking.  Rafting.  Climbing.  Slamming the mountain bike into things.  Trail running.  Ultra trail running.  Oh - triathlon looks good!  Ironman.  Beyond iron man, extreme iron man.  Celtman .  Double Brutal .  Cross country mountain bike racing.  Ultra matrathons.  Judo.  Karate.  Boxing.  Cage fighting.  Swimming.  Sea swimming. As time past I got better and better, fitter and faster.  I peaked, and then gradually slumped down until my lower back made moving fast something I thought twice about.  My first ten minutes of most days are hobbled around like I'm on stilts, my Achilles tendons tightened to crossbow torque. That's just what happens when yo