If doing 2 compound exercises at once with cable squat shoulder press was not
difficult enough you can add a balance component by standing on dual BOSUs.
While the dual BOSU squat shoulder press may not be a reason to go out of your
way to put the BOSU balance trainers in position, if the workout is already
involving dual BOSU balls, you can add them to the mix to place extra demand on
the 'other' leg muscles such as the adductors and abductors which are forced to
work more by balancing on the BOSUs.