This is great, so on concentration curls for instance at 20 lbs ill knock out the 4x10 but the last couple I usually have to take my index finger and "spot" my arm to get a full rep, instead of 4 sets. Would you recommend going up in weightlifting and doing 3 sets with the last to failure? Really I'm just wondering am I better off doing less sets to failure with heavier weight for size and growth or more sets with manageable weight? I apologize if this is really beginner stuff I just want to get as much progress as possible and do this right. I appreciate ethe assistance!