I hire electricians regularly. Driving a grounding rod is physically demanding. Moving conduit and hoisting it overhead for long runs is demanding. Carrying tools around, mounting light fixtures…and this is for light commercial work. It’s definitely not easy on the body and why older electricians want to transition in to design and engineering as opposed to field work.
These things are relatively physically demanding if your baseline is sitting at a desk.
But hammering a rod into the ground for 15 minutes, or holding some weight over your head, or carrying weight in your toolbag are not things that break your body down; they build your body up.