Fitness people are all around a heavy hammer, holding a heavy hammer wrist flexion and extension, how to do it specifically?

Positive winding weight hammer: one end of the rope is fixed in the middle of the stick, and the other end is weighted, so that both hands are raised horizontally without touching the ground. Stand with your feet shoulder width apart, with your hands (hands up) level, put the stick flat on your chest, turn the stick back and roll up the rope. Pay attention to the movement process, the knee joint and elbow joint should not be overstretched, naturally straight or slightly flexed, chest out and abdomen in, chin slightly retracted, and you should not shrug your shoulders and explore your neck. The counterweight is gradually increased, the movement is continuous and slow, and the breathing is stable. This action can exercise the wrist extensor. Wrist flexion muscles can be exercised by twisting the heavy hammer and holding the stick backwards.

Forehand wrist flexion and extension: short barbell (small straight bar) is recommended for standing posture or sloping board. It is more beneficial to protect the joint by alternately twisting the wrist (flexor forward and extensor backward) in a vertical state. The wrist moves like a heavy hammer, but it is more concentrated on the forearm. It is not recommended to use heavy objects when the forearm is placed on the bench and thigh, and it can be used as the ending action of wrist flexor training (the special training of professional athletes is not discussed). Attention should be paid to extensor muscles. Wrist pain caused by sports injury is mostly due to excessive tension and fatigue of flexor muscles (extensor muscles are relatively weak and lack of strength).

Please correct me if there are any mistakes. There is something about which muscles are trained by forward and backward winding in sports anatomy, but it can't be guaranteed to be correct.