You should have a bit of natural fitness before you even start preparing for that sort of journey.....
Unless you had a dump half way round, got lost, or were carrying your girlfiend while wearing diver's boot on your 1.5 miler, then 12:50 is the sort of time that asthmatic 50 year olds with zimmer frames might be aiming for.........
Take a look at this weblink to give an idea of Engineer trades as part of your basic Combat Engineer training...
http://www2.army.mod.uk/royalengineers/ ... combat.htm

