Social jetlag describes the habit of having two separate and distinct sleeping patterns. It’s often the case that this disparity occurs between very separate weekday and weekend routines, although it can of course occur in other circumstances as well.
So why is this a problem? Your body has a clever built-in system called the circadian rhythm, which signals to your body when it’s time to sleep. Your circadian rhythm is sensitive and if you develop a lifestyle that is often out of sync you could be compromising your sleep health. For many... (read the full article here).
Sleep Cycle, with millions of users worldwide, has built up what is likely to be the world’s richest repository with data reflecting global sleep habits. They have many interesting articles about sleep that are worth checking out on their website.