As expected, rheum and endo are usually light in terms of workload and weekend/night coverage. All others pretty much suck especially in first year. It also depends if you're going to a research-oriented program or a clinical-oriented program. And of course, alot of program-specific logistics (inhouse vs home call, number of fellows, protected research time, continuity clinic responsibilities, involvement of staff, residents helping out on heavy services ....etc)
I'm finishing up my hem/onc fellowship and I can tell you that my 1st year of fellowship was worse than my IM internship. I had fewer weekends and more calls. on top of that you're preparing for the boards and you're trying to learn your new specialty. Things got better half way through fellowship with more research and electives but overall, and contrary to common misconception among IM residents and med students, your lifestyle and workload is not going to be all that different in fellowship compared to residency.
