Most Canadians will enjoy an extra hour of rest on Sunday when they allow their clocks to fall back one hour as the shift is made to standard time.
Experts warn, however, that what feels like a gain to most can usher in a time of prolonged pain for those who struggle to get enough sleep.
Colleen Carney, director of the sleep and depression lab at Ryerson University, said insomnia sufferers may find their already problematic sleep patterns are crippled even further by having an extra hour in which to toss and turn.
"When you spend more time in bed, it's like telling your body, 'oh, you don't need more sleep, you need less sleep because you're less active," Carney said in a telephone interview. "People with insomnia will be excited by it, but the reality is that they get absolutely no benefit from this at all."
A night of extra sleeplessness is exactly what the average insomniac doesn't need at a time of year that's already rife with pitfalls, Carney said.
The earlier sunsets that accompany the shift to standard time can have a powerful effect on even those who enjoy eight hours of sleep each day, she said, adding longer periods in darkness are well-documented downers for large swaths of the population.
Those who are prone to insomnia, she argued, are even more susceptible to the low moods and other seasonal disorders that surface during the winter months. Those disorders can exacerbate their inability to sleep, touching off a frustrating cycle, she added.
Carney suggests insomniacs take a slightly different approach to the shift to standard time than their less sleep-deprived peers, only moving their clocks back after waking up at their regular time on Sunday morning rather than adjusting their Saturday bedtime.
"There'll be a little bit of sleep drive built up, and they won't get that extra hour in bed," she said. "They actually will be a little bit more primed for sleep."
For the rest of Canadians, however, Carney said the return to standard time is a bonus. Those who don't struggle with sleepless nights should revel in the rare opportunity to gain an extra hour of slumber, she said, adding research suggests most people could use it.
While Statistics Canada released data last year suggesting Canadians 15 and older got an average of eight hours and 18 minutes of sleep per day in 2010, Carney said at least two thirds of Canadians are falling short of their ideal daily sleep targets.
University of Montreal sleep researcher Julie Carrier agreed, saying the weekend time change will give most Canadians a needed break.
While the adjustment may not come easily, Carrier said the average body will respond naturally and positively to the chance for extra rest.
"The natural tendency of your biological clock is to go a little bit later every day, so it's way more easy to go to bed a little bit later and wake up later also," she said.
Clocks fall back at 2:00 a.m. on Sunday except in most of Saskatchewan as well as parts of Quebec, Ontario and British Columbia.
Note to readers: This is a corrected story. An earlier version incorrectly suggested this weekend would bring a shift to daylight saving time.
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