I don't think it matters who you are and what state your knees are in. A survival course where you average 37.5 miles a day over rough ground, on foot, is going to hurt!
Do you think you may have exaggerated the mileage, just a tad?!
BV
Bloody hell I knew somebody would reach for the calculator. Pedant.
Anyway, I never, ever, in all my years have exaggerated and never ever will till the day I die.
It bloody felt like 450 miles. I definately remember moving only at night (did the course in Feb so was dark for a good 12 hours) and we yomped for most of that. This is the older RN/RM SMAC AIR 424 course BTW not the RAF version.
Post survival course most aircrew do indeed balloon in size, mainly on account that they hadn't had anything to eat (excpet a squirrel or chicken) for 12 days during the course.
All the same, the bloke with the gammy leg lasted less then 48 hours and he thought he was fully fit.