Ready or not, Saturday, March 11, is the night to move those clocks ahead an hour for Daylight Saving Time.

The Medical Director for Calgary's Centre for Sleep and Human Performance Dr. Charles Samuels says it's not so much the one hour change that affects us.

"It's the fact that we go into the weekend where we make the time change quite sleep deprived," he says. "So, in North America about 30 per cent of the population runs around with a five to ten hour sleep debt on a weekly basis."

Dr Samuels says some people feel it through the week before the time change and they get worried and concerned about the loss but, he says, it's really about the cumulative loss of sleep that's accrued going into the week.

If someone is bothered for a longer period after the change he says it's not really the time change that's causing it.

"That's just a demonstration of either that they have a sleep problem and this is making it worse by losing that hour or that they are just not getting enough sleep, so it can be a case of their sleep quality not being good or they're just not getting enough sleep," Dr Samuels says. "And the other people are getting enough sleep and they're not bothered by the one hour time change."

He says it's really no different than getting on a plane and flying to Regina, if you're well rested.

Dr Samuels says your best bet is to take it easy Saturday night and you should be totally good to go again by Tuesday at the latest.