Strange sensation called “hypnic jerk” or “sleep start,” reports

While the feeling might be startling, according to Dr. Reena Mehra of Cleveland Clinic, it’s usually nothing to get worried about.
“A lot of folks have experienced this, it’s not something that people should be overly concerned about or think this is a serious condition,” said Dr. Mehra. “I think probably everyone can attest to the fact that they’ve experienced this at some point in time in their life.” ?