Polyphasic sleeping
Can you survive on two hours’ kip? Polyphasic sleepers believe so. They sleep in short bursts every few hours to cut down the overall time needed. A normal night’s sleep is divided into four or five cycles of three main phases: light sleep, deep sleep (the most restful) and rapid eye movement (REM) sleep. The reasoning behind polyphasic sleeping is that you’re so tired you fall straight into the final two cycles. The most challenging regime is the ‘Uberman’ — six 20-minute naps at four-hour intervals. Sarah McCulloch, a student at London South Bank University, used Uberman while preparing for exams, for periods of up to four months at a time. Instead of her usual eight-and-a-half hours, she’d sleep at 4pm, 8pm, midnight, 4am, 8am and midday. ‘You have a few days of feeling terrible, but you adjust and it becomes like regular sleeping.’ The hardest thing, she says, is fitting it around a social life — she once had to nap at a restaurant. ‘It’s not that practical, but if you have a deadline to meet, you’ll meet it.’ Dr Guy Leschziner, consultant neurologist and lead clinician at the sleep disorders centre at Guy’s and St Thomas’ Hospital, cautions that it’s not for everyone: ‘Whether you sleep half an hour every two hours or a full night in one go, our sleep requirements are genetically conditioned. Some people need more, some people need less.’