What results could be expected from a polygraph if you are told to place your hands on your knees and do not move, causing the blood pressure cuff, which is too high to be in direct contact with the body and chest straps.
I'm reading your post with the assumption that there should be a comma after "which is too high." In such a case, with the cardio cuff in contact with the chest, one would expect the examinee's breathing to contaminate the cardio tracing.