If you want to become a force of nature, you need to interact with the forces of nature. - Erwan Le Corre

Your body will never be more connected to your mind than when something is at stake. That's how you measure the value of a movement: by its consequences. Climb a tree, throw a rock, balance on the edge of a cliff-- you lose focus for a fraction of a second, you're screwed. It takes a very affluent and indulged culture to convince itself that standing around in weird poses is exercise.

I meet men all the time who can bench 400 pounds but can't climb up through a window to pull someone from a burning building. I know guys who can run marathons but can't sprint to anyone's rescue unless they put their shoes on first. Lots of swimmers do laps every day but can't dive deep enough to save a friend, or know how to carry him over rocks and out of the surf.

It was all practical stuff. Why? Because that's the way you train soldiers: practical stuff. Soldiers don't freaking need to do a flag, you don't need to do handstands. You need to run and sprint and vault over obstacles. They need to balance on stuff, and they need to climb to crawl to lift and carry, throw and catch. They need to do all these things. They need to fight, to swim.