Current Hopkins student (not an MPH, but I have acquaintances in the program). A lot of students fulfill the "practicum" with a normal class that has practical elements. There are a few of these classes that count, and they're not more strenuous than a normal class, I believe.
I think it's overall a good program with a few pitfalls. Would need to know a bit more about your interests and background to determine if they'd apply to you.