They help to strengthen the neck muscles. In isometric exercise, there is very little or no joint movement. In these exercises, the hand provides resistance. It is important to begin these exercises in an erect position. So, sit up straight and slightly tuck your chin before beginning.
Place your palms at the base of the head and apply light forward pressure. Meet the resistance with your head and neck.
Side bending :
Sit erect with your head in a neutral position; place your palms above/around the ear. Apply light pressure with the hand and meet the resistance with the head.
Place the index and middle fingers of both your hands in between your eyes, and apply light backward pressure, meet the resistance with your head and neck.