Gu Quanxi, a native of Hebei who is almost 90 years old, loves climbing tall trees. According to Gu Deyun, the old man's son, the old man can climb to the upper branches of the walnut tree in the family garden from the bottom of the trunk. He used to scale the trunk using only his hands and feet, says the son. Now the old man has been advised to use a ladder.

Gu cannot explain the appeal of his unique hobby but simply says that he loves it. His agility astonishes his neighbors, who say he looks much younger than his true age.

The old man chooses to climb tall trees despite his family’s repeated warnings. He has a set of rules of his own to keep healthy. He prefers sweet potatoes to rice and meat. He drinks only hot water, he loves to eat brown sugar, and he sleeps in a heated bed whatever the season.