Fat definition of heavy work. I work as a nurse in a classroom of disabled kids. (Just one is my patient) the classroom aide...a moon...is filling out a report and one of the questions is about what the level of work difficulty is physically. Rest (ex. Paperwork), Light work (ex. Retail), medium (ex. waitressing), and heavy work (ex. Roofing). She selected heavy work. She is a classroom aide! Occasionally she has to lift a 40 lb kid to a changing table, like once a week. No wonder she needs cookies and soda every day at 9am since she is expending so much energy at work!