I am now 70 years old. I now live in the USA. I joined in 1970 as a very fit individual. I was running 10 miles a day and gym training. I am now 70 and recovering from failed knee surgery in 2016 and I am getting core fit for hunting next year. I have a 30lb pack and walk 3 miles per day working up to 10 miles in 3 months I hope. I am a certified firearm instructor. Joining RM at Deal in April 1970. Moving on to CTCRM with great reports I was recommended by Troop Sgt I apply for officer training. I turned that down. 9 miler was a piece of cake as were 30 foot ropes etc. As I moved on I was getting foot trouble. Our boots were DMS boots (30 shillings a pair I am told). No steel shank and not water proof. I bought a pair of ex USPara boots which helped me out greatly. After 1 week I was caught and fined 10 quid as they were not issue. Eventually withdrawn from training and sent for X-Rays. Turns out I have flat feet and deemed unfit for the 30 miler. I was medically discharged in mid 1971. Now moving on some 10 years I wore those same boots to compete in a pennine mountain 24 mile challenge with a light pack. I completed in under 5 hours wearing those Para boots. I have always regretted not making the grade but convinced I could have done. Turns out DMS boots did for many in the Falklands. Still a Bootneck in spirit. Moral of the story is you have to work smarter to get through. Good gear though helps greatly.