I've been training arms and seen some developments however after training last monday I trained biceps felt I gave them a good blasting, had my training partner keep an eye on form. However the day after my rear delts and front head felt they had a work out the day after my biceps got it. I am a little worred that my shoulders took most of the benifit of the work out. Could you give me tips as to Isolate the bicep more??? As Im scratching my head having used preacher and seted curls.