Meaning: Exhausted without feeling the heat, just cherish the long summer days.
From Bai Juyi's "Watching mowing wheat"
Excerpts from the original poem are as follows:
Ding Zhuang was in Nangang when he went to pay for the farmland. The foot steams the earth atmosphere in the summer, and the back burns the sky. The strength does not know the heat, but the summer is long. There were poor women again, holding their children by their side, holding their ears in their right hand, and hanging their basket in their left arm.
Translation:
Accompanied to the fields to deliver food, men work in Nanshan Hill. The feet are fumigated by the ground heat, and the back is burning with the sun. Exhausted and not feeling hot, just cherish the long summer days.
Another poor peasant woman was seen, holding her child with her. He held the wheat ears in his right hand and hung a broken basket on his left arm.