Robert - just to prove that WE ARE BUT HUMAN and to be honest about my advice above about 'personal control'....
I have just returned from an 8 day teaching tour that included local clubs and two visits to a university. Despite my health history i did my best and am proud to say that i have had e-mails from various students (both club and Uni) that have thanked me and said they learned things!
BUT - did i come home unscathed = NO!
Why - was it Karate = NO!
One of the senior Karateka I visited is a very accomplished Musician and for several decades they have organised a 'Jam Night' when musicians from all over the City get together and play brilliant Music and have fun. I have attended everytime i visit for many years. I went along - they - as always - made me welcome and bought me drinks - (I suspect you can see where this is going!)
One of the lovely ladies whom attend asked me to dance - me being me i started 'Dad Dancing' - caught my foot under a table leg, tried to turn and CROCKED my knee.
How dare i preach to you about 'personal control' eh?
I am currently limping like a tortoise with one leg!