Yes, I was referring to residents. In all residencies you "rotate" through different topics or subspecialties. Either once a month or every other month you will be doing another part of your specialty. Medicine residents generally do 6-10 months of general ward medicine (depending on program and year). The rest of the time is spent in cardiology, GI, rheumatology, endocrine, etc. Some of these are inpatient services which generally means being on call and working weekends. Some are ambulatory, which means 8-5 weekdays only.
This is true in other specialties as well: Surgery (general, CT, transplant, laprascopic, etc), Ortho (general surgery, orhto trauma, etc.), Radiology (Neuro CT/MR, body CT/MR, Interventional, chest, ultrasound, etc). You get the point. By nature, some are more time intensive than others.