Clock Change: Is ‘Sleepy Monday’ the Most Dangerous Day of the Year?

Posted by Dr Sophie Bostock on 22nd Mar 2022

Clock Change: Is ‘Sleepy Monday’ the Most Dangerous Day of the Year?

A word of caution for Monday 28th March.. take special care if you’re going out on the roads, operating heavy machinery or attending a hospital appointment..

The Monday after the clocks are rolled forward in the Spring has been coined ‘Sleepy Monday’. The first working day after the clock change has been associated with a variety of safety and health risks including...

●a 24% increase in the number of heart attacks and strokes, versus a typical Monday

●a 16% increase in road accidents and a 6% in fatal traffic accidents

●a 5.7% increase in mining accidents, and a 68% increase in the severity of those accidents

●an increase in missed hospital appointments and higher A&E visits.

If you have a court date booked, you might want to postpone, since judges have a tendency to give harsher sentences on Sleepy Monday. There is also a spike in ‘cyberloafing’; entertainment related internet searches during work hours, and a peak in stock market volatility.

‘British Summer Time’ sounds like good news, but the impact of suddenly shifting clock time has unwelcome consequences for our sleep and physiology.

Why is British Summer Time bad for the body?

Our bodies are programmed to run on a 24 hour cycle of activity, called a circadian rhythm. Every cell and organ in the body operates its own internal clock. Sunlight provides a cue, via a master clock in the brain, which helps to keep all of these body clocks working together, in sync with one another and the light/ dark cycle of the sun.

When we suddenly move the time on our clocks forward by an hour, our internal biological rhythms can become out of sync with sunlight’s light/dark cycle.. This makes it harder to wake up in the morning, and means we’re less sleepy at our normal bedtime. Not only does this interfere with getting enough sleep, but it also means that all of our other circadian rhythms - in appetite, immune function and blood pressure etc - are out of sync with our typical daily routine. When we wake up at the new clock time, for example, this may be before the cardiovascular system is ready. Waking early puts increased strain on the heart, which may help to explain the uplift in heart attacks, stroke and atrial fibrillation on Sleepy Monday.

Even before the Spring clock change, many people are getting fewer than the recommended 7 or more hours of sleep. When we ‘lose’ an hour of sleep on top of an existing sleep debt, the effects of that 1 hour of lost sleep are exaggerated, and can make some people excessively drowsy, which could contribute to their accident risk.

The Spring clock change is particularly tough for teenagers and anyone who is more of a ‘night owl’. Night owls have a circadian rhythm that runs a little slower than average. This means they usually struggle to wake up early and naturally have a tendency to stay awake late at night. When clock time is advanced, night owls will struggle more than most to adjust.

So how can you prepare for the Spring clock change?

  1. Get a bit of extra sleep this week to make you more resilient to the effects of losing an hour’s sleep at the weekend. This ‘sleep banking’ will help the body to adjust more easily to the new timezone.
  2. To help you body clocks transition gradually to the new timezone, you could start getting ready for bed 20-30 minutes earlier and getting out of bed 20-30 minutes earlier this week
  3. On Sunday morning, try to avoid a lengthy lie-in – this will only push your bedtime back and make it even harder to get out of bed on Monday morning.