Yes it depends what type of zercher you do. True zercher ala Ed Zercher from the floor,to the quads,hook arms under stand up,then reverse this movement,Zercher squats off of hooks in a squat rack,hook arms under the bar,stand up straight,squat x number reps,rerack and my favorite starting from the pins on a power rack,get into the bottom position hooking the arms under and stand up,back down and repeat.You need to be more specific but it will vary from person to person unless your talking an absolute max then you may look to what some strongmen competitors do in their training.