Định Nghĩa và Ý Nghĩa của "hollow leg"

What is the origin of the idiom "hollow leg" and when to use it?

The idiom "hollow leg" is a humorous expression used to describe a person, usually a young one, who seems to have an insatiable appetite and can eat large quantities of food without gaining weight. The origin of this idiom is not precisely known, but it likely derives from the exaggeration that someone's leg is so hollow that it can hold an enormous amount of food.