This is an individualist approach, a productivist one and a validist one. I see you point : people shall prepare But the next question is : to do what ?
If you want to prepare to run: run if you want to prepare to climb : climb if you want to prepare to fight : fight
This not an RPG, muscles could act counter-productively (it's weight more, and need more calories).
But most importantly, prepare to do it collectively. Some of us have the health and condition to prepare to do some of this, and may need to be recall that they have a responsibility to do so, because some of us don't. Futhermore in most situations it's better to be 3 people not well prepared than one fit. So take care of you community and make it grow