People sometimes suddenly feel a foot in the air and are awakened during sleep. This is a common physiological phenomenon called sleep jerk or myoclonus, which tends to occur when they have just fallen asleep and when they are about to wake up. Because neurons in the higher cerebral cortex are in a state of inhibition during this sleep stage and lose control of the lower centers, resulting in the lower centers being more active, even a mild electrical stimulus may cause impulses to be issued and cause muscle contractions, which may occur in both the hands and feet. When the muscle contraction appears in the legs, it may cause a transient leg twitch, and the patient may feel a step in the dream state and thus be awakened. This condition does not require excessive anxiety and has no effect on physical health. If frequent episodes occur, it means that the patient may experience fatigue or anxiety and emotional tension, which can be relieved by self-regulation.