I agree with PsychApp. You of course need to balance out getting good training (which in my opinion involves doing overnights etc), but in our culture wellness issues that are systems-based often get translated into terms of individual culpability. So, for instance, if you feel burned out by doing frequent 24-hour shifts, having little time to spend doing things you enjoy, and carrying a high workload in a relatively unsupportive environment you may be offered individual tools (like meditation, exercise, Yoga) or platitudes, but the source of the distress is the poor system that is in place and often "wellness" programs don't touch that.
In short, choose a program that puts its money where its mouth is on wellness as evidenced by satisfied residents managing reasonable workloads. Pay attention to exactly what each program has on offer in terms of call, patient caps, leave policies, elective policies etc. and contrast and compare. Also feel free to ask residents for their opinion on those issues. When I was interviewing I was surprised by the frank answers residents gave me, especially in terms of program weaknesses. As a resident I came to understand that you don't want colleagues to feel tricked into coming to your program, so you do want to provide a realistic picture of the good and the bad. That makes the current residents a very valuable source of information.