History has many accomplished nappers.
Leonardo Da Vinci took short naps every few hours; Napoleon Bonaparte dozed on his horse. And very wise they were, too. Lack of sleep causes the body to produce more of the hormone cortisol, which gives us energy but restricts production of human growth hormone — limiting the body’s ability to repair itself.A 2008 Stanford University study found that fruit flies’ immune systems fought invading bacteria best at night. This backed up the theory that our bodies use dormant hours to regenerate and fight disease (by producing immune cells called monocytes).
Source - Daily Mail