Sunbathing or overheated?

[YourLostSock]

Newbie question. I’m raising chickens for the first time. 5 Americana (Easter Egger) chicks, which are about 3 and a half weeks old. Today was the first time they went outside. They played around in a fully shaded spot of the backyard. As I was carrying/dragging their brooder bin back, they crossed a sunny area and immediately, within seconds they all flopped down in the bedding, on their sides even. It is about 81*F outside right now, should be comfortable weather for them. This is the first time they have been in direct sunlight.
Were they overheating or sunbathing? I’d like to know for future reference.

 

[Chick-N-Fun]

She looks overheated! When taking them out on mini field trips, I would recommend a shady area and provide them with fresh cold water.

 

[Wetmorechick]

I would say, sunbathing!

 

[centrarchid]

Look like sun bathing in picture.

 

[rosemarythyme]

If they all dramatically flopped, sunbathing.

 

[centrarchid]

If hot, look for panting and dropping both wings holding them out a bit so the their "arm pits" are exposed to airflow.