At first, you can hit ordinary sandbags with correct movements. After getting used to it, you can slowly change to hitting heavy sandbags, and then slowly change to hitting banana trees and the like (hitting banana trees is not recommended. , unless you rely on practicing this for a living). But remember not to be too impatient when training. Otherwise, it will cause harm to your own limbs. If you want to improve the hardness of the tibia, you can gently hit the tibia and facial bones with a hard object every day, or roll the iron rod in the middle of the barbell back and forth on the tibia or facial bones, but you should supplement it with safflower oil or distilled wine after finishing. Application of medication. And be careful not to hit too hard, otherwise you will be easily injured. As for whether it is scientific or not, I can answer you this way. The bone hardness of Thai Zhengzhong Muay Thai masters is indeed amazing, but it is an indisputable fact that they generally have a short lifespan. The reason is the damage caused to the internal organs and bones of the body through normal training. Therefore, there will still be harm, but as long as you pay attention to gradual progress and stop in moderation, you can strengthen your body without harming your body.

This is what a senior told me before. There may be something wrong, please give me some advice!