Plenty of animals can sleep upright, such as horses and various livestock.
But what about people? According to a recent BBC News article, it's possible but not always comfortable.
"We can sleep in a chair. We can sleep standing up, but we are not as good at it as other creatures, for example birds," Derk-Jan Dijk, a professor of sleep and physiology at the University of Surrey in England, told BBC News .
The article looks at a group of Buddhist monks who during their four-year retreat spend nights sleeping upright for less than five hours. This position can be fine for quick nap, but when it comes to Rapid Eye Movement (REM) or "active" sleep, it becomes harder to remain upright.
"In Rapid Eye Movement sleep we lose the tone in our muscles, which makes it difficult to stand up or even sit up," Dijk told BBC News .
However, the monks claim someone who is well-attuned can use their sleeping time to remain upright for meditation. Of course, sleeping upright is not recommended for everyone — just as sleeping for less than five hours a night isn't recommended for everyone.
Getting enough continuous quality sleep contributes to how we feel and perform the next day, but also has a huge impact on the overall quality of our lives.