The second thing is that your spine health and joint health has got to precede everything else you’re doing. If you centralize your training on the integrity of your spine, you will see exceptional progress everywhere else. If your joints, or your spine, cannot move in particular fashions, it isn’t because “you’re tight and can’t do it,” its because you are not prioritizing the most important steps to building your body. In order for a hip to function as a hip, it needs to be able to do more than laterally rotate, it needs to understand internal rotation, adduction, abduction, extension, flexion, the list can go one. Muscles won’t work as well as they can if the joints don’t work well. If you want ‘function’, show me joint control, thats my second point. for something to be functional, the joint has to understand its’ function, and the muscles surrounding it must understand their job in order to perform said function. Get it? You are only as functional as your nervous system allows you to be. And if your nervous system cramps out when I ask you to bend your knees to 90 degrees and hold it, it’s because you haven’t accumulated enough neural drive at that angle.
Fortunately for all of us, joints move in various angles and to multiple degrees, and your job is to work your body in as many degrees of motion as possible. If you can do that, you’ll have a much larger success in moving better, producing power, and controlling yourself. So if you can’t perform basic shoulder flexion to 180 degrees with a straight arm, what makes you think you have interest in loading your glenohumeral capsule with weighted presses? Or even better-downward dog? Muscles all have several functions, as agonists, antagonists, and synergists of movements, but if someone’s joints don’t function as evolution intended, how can you tell me that their exercise is functional?