Under normal circumstances, the back is an inactive place in the human body. Therefore, hitting the tree on the back of the waist can promote the blood circulation of the back of the waist, improve the local microcirculation, improve the nutrient supply to cells, and then promote human health. Don't you think those royalty in TV series are people who beat their legs and backs, passively exercising their bones and muscles and promoting their health? Using big trees, self-impact is a convenient way to keep fit, which is worth a try.