Sleeping Until Noon on Saturday Doesn't Always Win Back What You Lost: Specialist Àlex Ferré Masó Compares Sleep to a Washing Machine Programme

The clocks went back an hour and revived the old delusion once more: everything lost from Monday to Friday gets won back by noon on Saturday. Sleep medicine specialists have bad news about this arithmetic. It doesn't always come back.

First, the hour. Dr Mira Berenguer, head of the department of brain health, sleep and performance at the ZEM Wellness clinic in Altea, explains that the internal clock governs the cycle of wakefulness and sleep, body temperature, hormone release and alertness. That's why even a shift of just 60 minutes needs a period of adjustment.

Neuropsychologist Valeria Medina of NeuronUP says that for some people the changes in sleep and increased drowsiness last around a week. But winter time, according to her, suits the biological clock better, because morning light coincides with the start of activity. So the October change is a good moment to fix your rest, not an excuse for it.

Dr Àlex Ferré Masó, a sleep medicine specialist, compares sleep to a washing machine. "Every person has their own sleep programme," he says. If the cycle is cut short, it's the same as taking the laundry out before the programme ends. It comes out, but it isn't clean. And he adds something that anyone who proudly says they've slept little for years should hear: the sentence "I've always slept my hours" doesn't mean you sleep enough.

The real problem, according to him, isn't the October shift but what we do every week. It's called social jet lag: the difference between working days and the schedule from Friday to Sunday. His example is an ordinary working day. A person needs 8 hours, goes to bed at midnight, gets up at 6 for work. That's two hours of debt a day, ten hours over five working days.

Can a debt like that be paid back over a weekend? Ferré Masó says the body "won't always manage to recover", especially in people whose bodies are used to waking early. Recovery mechanisms exist, but they can't always make up for what's lost. The best indicator of whether you're sleeping enough, according to him, is waking at the same time every day.

The advice from the two of them is so simple it sounds boring: a regular schedule, dim light in the evening, a walk while it's daylight and regular exercise. Dr Berenguer says that from a chronobiological point of view this makes more sense than a long sleep on one particular day. So Saturday until noon is no cure. It's one more programme we stop halfway through.