Waking up in the middle of the night and can't get back to sleep? Sleep specialist Francisco Díaz García's advice: get out of bed

You wake up in the middle of the night, stare at the ceiling and tell yourself: just relax and you'll fall asleep. Half an hour later you're even more awake. According to sleep specialist Dr Francisco Díaz García, that effort is exactly the problem. Sleep can't be forced, and lying in bed straining to fall asleep keeps the brain in a state of alertness.

"Sleep isn't something we do, it's something that happens when the brain lets its guard down," he says. The more you fight, the further away you push that guard.

There's a deeper trap too. When waking at night keeps happening, the brain learns to associate the bed with frustration and sleeplessness. Experts call it conditioned arousal: the bed stops being a place of rest and becomes a signal for restlessness.

The advice sounds counterintuitive: get up. Go to another room with dim, warm light and do something calm and low-stimulation - read, listen to a podcast or watch something light. Leave work, email, social media, thrillers and the news for the morning. If you have to look at a screen, keep it dimmed and away from your eyes.

You go back to bed only when you're genuinely sleepy, and if you wake up again - repeat the routine. According to Díaz García, within a few weeks sleep usually comes faster and becomes more stable. How many of us, instead, reach for the phone first the moment our eyes open at three?

If the problem doesn't go away, it's time for professional help. Chronic insomnia is when you sleep badly at least three nights a week, for longer than three months, and it disrupts how you function during the day. It can be treated, often without medication - and stimulus control, the technique described above, is one of the first tools in cognitive behavioural therapy for insomnia.