Re: Tomiki Kenji's Attribution of Ueshiba's Skill to "Muscular Training"
I think some people here may be assuming that "isometric" means to isolate a single muscle group, which it does not. Isometric drills are any static posture that requires opposing forces to maintain, such as the iron cross, L-sit, or holding a partial squat.
An isometric muscle contraction is a contraction that maintains the length of the muscle instead of shortening it.
Isometrics have absolutely nothing to do with muscle isolation or bodybuilding, and isometric training is not, as a general rule, part of the training protocol for bodybuilders. It is much more in the wheelhouse of strongmen, gymnasts, and other bodyweight enthusiasts.