SINGAPORE - Those who cherish their eight hours of beauty sleep will frown at Mr Josh Quah's regular night-time routine.
From midnight until at least 3am, from Monday to Wednesday, the 26-year-old can be found seated in front of his laptop with his headphones blaring.
He is writing electronic music tracks. He gets by with just six hours of sleep, waking up by 10am for work as an events manager at Lowercase cafe, located at Lasalle College of the Arts.
His reason for staying up so late is to "flex my creative muscles after work. I need to keep my skills going and improving", he says.
Mr Quah, who is single, makes up for the lack of rest by sleeping saner hours the rest of the week.
SundayLife! found many night owls like him, in their 20s and 30s, who hit the sack only in the wee hours of the morning on a regular basis.
Some hold day jobs but keep their creative juices flowing at night, when they say they can concentrate better.
Others stay up because of highly addictive hobbies such as social media and video games.
Almost all rely on a steady supply of coffee the next day to keep them awake. General practitioner Colin Lim calls these night activities "distractions" that have "messed up human beings' sleeping cycles".
Social media junkie Tysha Khan, however, would argue that she has a naturally different sleeping cycle.
"I'm just the type who is late to wake up and late to go to bed," says the 21-year-old undergraduate, who sometimes turns in only after the sun rises.
Another person who claims to be nocturnal on a daily basis is Mr Hasnor Sidik, 33, W Hotel Singapore's artistic director.
He usually sleeps at 3am on weekdays due to the nature of his work, but does not use the weekends to catch up on his sleep.
"I sleep at 6am on weekends. I am up to sip, play and flirt," the bachelor says with a grin, referring to his partying habits.
He claims his concentration is never affected as he has "very good tolerance".
Having wives and young children does not stop some men from staying up till the wee hours of the morning because they cannot do without their video game consoles, roti prata supper or a beer.
Their wives, they say, are resigned to their habits.
Nightbird Khairul Amin, 34, a manager at North East Community Development Council, says that in order to hang out with his friends late at night for suppers, he has to "pacify" his wife "by taking her out for a date the day after, or simply engaging in some form of negotiation".
Events management company founder Eric Kwan, 34, who plays video games nightly until about 3am, has to rely on his wife to wake him up for work each morning.
"She either physically pushes me out of bed, or sings some irritating song that awakens me," he says.
Finally, there are also those who exercise late at night and go to bed at 2 or 3am.
They find the solitude of the night more conducive to a workout than the hustle and bustle of the day.
Public servant Tan Yi Shu, 31, is one such person.
He exercises four times a week. Two are late-night exercise sessions, in the form of a run or a cycle, which end at midnight.
"There is less traffic at night so the air is fresher, and it is also much safer to cycle. I get to reflect on my day when I run late at night too," says Mr Tan, who is single.
He goes to bed by 2am and rises at 7.30am to prepare to go to work.
Doctors say night owls who get by on just three to four hours of sleep are straining their bodies.
Says general practitioner Theresa Yap: "Eventually, this will take a toll on their health. When their bodies lack sleep long- term, they are increasing their blood pressure and increasing their risk of getting a stroke or a heart attack."
Consuming coffee to keep their energy levels up is also unwise and too much of it could lead to chronic insomnia, say doctors.
"Whatever your poison is to stay awake, it's just a temporary measure," says Dr Lim.
Doctors agree that the human body needs between six and eight hours of sleep, but there is no consensus on when is the best time to turn in for the night.
Some say sleeping late does not matter as it is the number of hours of rest that counts, but Dr Lim says it is best for people to sleep between 10pm and midnight.
"The later you rest, the more you are affecting your body's circadian rhythm. Man was made to sleep at proper times, so our bodies suffer when we don't follow these," he says.
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