Take bread.
You start the oven at 4am. By 5am it is hot enough for your meats. By 7am extinguish, by 8am start your bread and go until 6-7pm. Now you get to start your dough for tomorrow, typically working until 11pm.
Historically bakers were known to sleep in flour hoppers as they were spared some of the heat of the ovens.
Ancient people _always_ worked. There was no leisure weekends, no afternoons off.