I hate mithering the PT's in the gym,so i'll ask on here instead,(hopefully this isnt a stupid question),I've seen comments about heavier weights less reps and i know control and technique are most important,but,if say,im pressing 24kg dumbells,trying to do 5x12 reps.i might manage 12 on the 1st set,but the 5th set i'll only manage 4/5! should i use less weight and try to ensure i do the full 5x12,or keep going,or try to do less reps,or what? Obviously coz im only doing 4/5 on 5th set,im gettin knackered,so technique is prob suffering.(much as i try to keep it good). Also,should i put your answer to use with other lifting areas? ie. concentration curls etc.?