What factor contributes to the physical taxing nature of operating heavy machinery like an excavator, even when not performing manual labor?

Answer

Vibration transmitted through the equipment

Even when operating machinery, the job remains physically taxing due to the vibration transmitted through the equipment, alongside the need for situational awareness and repeated physical ingress/egress from the cab.

What factor contributes to the physical taxing nature of operating heavy machinery like an excavator, even when not performing manual labor?
jobcareerconstructionlaborphysical