First, this is posted by ex-military and is couched in the language of soldiers. I HIGHLY recommend reading it even if you have a problem with the language. That language was created for multiple reasons, not the least of which is ease of communication when there is no time to sit and discuss things...
I'll assume that we all agree that practice is necessary...
This article explains the reasons for practice (WHY) and the ways to practice (HOW).
http://graywolfsurvival.com/1238389/why-and-how-to-wargame-your-emergency-preparations/If nothing else, read the first warning: "
Discovering your abilities and shortcomings" which shows the need for practice.
I confess, I'm NOT in anything like full physical fitness, despite regular bike riding at cardio levels (raised heart rate and pushed to the muscle pain level). How about you?