Isometrics

[Fluidity]

Hi everyone I want to ask you guys if doing a full body isometric flex before workout is beneficial? The whole idea is that after prehab and warm up I would tense up every muscle in your body from a standing position. After tensing every muscle and holding it for a few seconds I would consciously relaxing every muscle to help the blood flow through the body. Along with that what about maximally tensing individual muscles? What do you guys think of this? Should I do a full body isometric flex?

Along with that what do you guys think of flexing muscles during a static hold? Like flexing my arms during a frogstand or the bottom and top part of a push up/ squat/ leg raise, etc?