People who are social and mingle in groups tend to be sleep deprived more than those extroverts who spend the same time privately, a study said.

The study in the Journal sleep, says that hanging out with large groups of friends would drain a person's energy and make them sleep deprived.

Researchers at the Walter Reed Army Institute of Research tested a group of 48 adults between the age group 18 and 39, and found that extroverts who mingled with outside groups reacted slower than those who had been alone.

The extroverts, who remained alone, tended to have good sleep in the night. The study could help the US military in shifting people on military assignments.