[Blarg]

For the strain you put your lower back through, you might be better served by something like yoga.

Otherwise, if you lift, you seem like the ideal candidate for strength-based work-outs. Low reps, few sets, and heavy. Not a lot of times per week, considering what you do for a living and that you need some recovery time. You can still get very strong that way.

If you do the typical bodybuilding high sets and reps, plus move furniture all the time, you'll probably wind up overworking and stalling your progress. And also, strength would be very helpful to you while the alternatives of building lots more mass wouldn't do anything for you and endurance is covered by your daily grind anyway.