Scientists say that groggy feeling you have when you're back at work on a Monday - could actually be social jet lag.
The study at Rush University in Chicago found that sleeping in over the weekend can leave us too tired for the start of the working week, with many remaining groggy until Wednesday. The immediate effects include poorer memory and reaction times.
The research also shows that over time, repeated changes to sleep patterns can also make you fatter and more likely to turn to cigarettes and caffeine. Results suggest that a shift in sleeping patterns of just two hours can leave you worse off in the week.
- Newstalk ZB