The anatomical characteristics of the human body cause it to function in a crisscross manner. The arm-and-shoulder mechanism on one side links diagonally through the torso mechanism to the hip-and-leg mechanism on the opposite side.
Think about what you're doing while walking, running, punching, throwing, and batting. Such cross-body linkages are foundational to human functioning and a big part of athletic movement.
One type of cross-body movement involves rotational core exercises, such as weight-plate chops shown here.
The strength and conditioning field is like no other. Coaches have bitter enemies and die-hard devotees – and sometimes a person will qualify as both depending on the day of the week. There are insane egos and there are humble, incredibly bright coaches who go unnoticed. Finally, there are a lot of coaches who people really don't get.