Subject opened the jaw once every 2 seconds.
The subjects opened the jaw maximally as fast as possible and repeated the movement for 20 times (1 set).
Three sets were performed with a 10-second interval in between. The exercise was performed twice daily for 4 weeks.
Furthermore, subjects were instructed to feel the strong tension in their suprahyoid muscles during jaw opening and were instructed to stop the exercise if they felt any abnormality in their temporomandibular joints.
Since the rest position of the hyoid bone appeared to have improved, this exercise may be especially useful in elderly individuals with a lower position of the hyoid bone at rest and those with decreased elevation of the hyoid bone during swallowing.