maybe this action could be more like vegeta vs goku, in the first fight they have, kinda like a agression bar,
you can push an certain amount of extra ki into the struggle,
what i mean is when you first initiate the struggle it drains youre ki,
when u want to give the struggle a extra boost you can push a key that will starts an bar that when its full you cant boost it any further, this will go with the screaming according to the show,
like it was in almost every fight, they can push it further than the strenght of the beam, but it will drain youre ki faster,
damn i suck in making sence