Most people don't know how to train properly, that's why the mainstream is going to the gym, I have news for you the gym started as a supplementary workout, the idea was to work on a weak group of muscles in an isolated manner to balance it with the rest of the body. It's not supposed to stand as training, same for many other popular practices...

Integrate instead of isolate - Strength, Flexibility, Coordination, Balance. This is how you gain real fitness and true freedom of motion.