Why does my husband keep twitching and jumping in his sleep?

Probably benign: Most people have had "sleep starts", a sudden jerk of the body, when falling asleep, or when aroused. This is a normal component of sleep. Repeated movements of the legs is periodic leg movements of sleep, a variation of restless legs syndrome. This can make the legs and feet twitch hundreds of times in the night; it can be easily treated by prescription medication.