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.

Julie Angel (2016). Breaking the Jump: The Secret Story of Parkour's High-Flying Rebellion, Arum Press