Daylight saving time: Does changing our clocks make us sleepy?

As the days get shorter and the nights longer, we prepare to fall back an hour as daylight saving time ends. Who doesn’t need an extra hour of sleep, right?

Across most of North America, daylight saving time ends Sunday at 2 a.m. as we fall back to standard time and regain that one hour of sleep we lost in the spring.

The extra hour we had in summer evenings is now shifted to the morning hours. That’s great for folks who are early risers, but not so much for those who commute daily for work and end up feeling like vampires since they end up not seeing much daylight for months.

The practice of daylight saving time really began to be widely adopted in 1975 as a way to save energy. Electricity demands were found to be directly related to when people go to bed and rise. Shifting the clock by an hour actually decreased the daily consumption of electricity. While these findings were refuted and much of the effects proposed were cancelled out by other electrical demands, daylight saving was still adopted.

But for many folks, it’s more of a headache then anything else. Studies have shown that there are more car accidents in the first few weeks after the one hour fall-back. Sleep patterns appear to definitely be disrupted. These changes appear to particularly hit students taking morning classes, shift workers and those who work long night hours.

“Sleep loss does impact mood, as well as reaction time, attention, memory and visual and motor acuity,” said Kimberly Cote, President of the Canadian Sleep Society and Director of the Sleep Research Lab at Brock University in an interview with Yahoo Canada News.

“That one night of sleep loss can have an effect not only on mood, but safety and performance.”

But when the clock is moved forward an hour in spring when daylight saving time kicks in, even greater negative effects are seen.

That’s because we find it easier to stay up late, and when its time to get up – one hour earlier than we’re used to – that morning grogginess can hit us hard.

In the fall when the clock is moved back, it is easier to fall asleep at the new time. If your usual bedtime is 11 p.m., and you go to bed at the usual clock time, you have actually delayed going to bed by one hour, Cote explains.

“Because you will be very sleepy by having spent an extra hour awake that day, you will fall asleep quickly and sleep deeply,” she said.

“In the morning when the alarm sounds at the new 7 a.m., you feel as though it is 8 a.m. You are well rested, having been in bed for 8 hours, and having slept well. If you went to bed at your usual time according to the old clock time, you end up getting an extra hour of sleep.”

So, what’s the best way to cope with the moving the clock in spring and fall?

Cote believes we can all lessen the impact of these time shifts by just making sure we get a good night’s rest on a regular basis and be concisely aware of appropriate bedtimes.

“My advice would be to make an effort not to lose that one hour of sleep in the spring by going to bed earlier that night,” she said.

“You can also make the shift easier if you change your bedtime by 15 minutes each night leading up to the change, over a four-night period.”