It takes it out of you when you have a day out of the ordinary. Maybe you went to the zoo with your family. All that walking, the heat, the sun, the driving, the general excitement, and all of that for 8-10 hours. It’s draining.
But the body is pretty awesome. If you do a few big “zoo” days every week, your body will adapt and those 10 hour days feel normal. You aren’t wiped out and you’ve gotten more resilient.
The body adapts. Just because it feels very difficult today, tomorrow, and the third day, doesn’t mean it will be difficult forever. You will adapt.