What if you’re not a morning person?

But while “larks” happily wake an hour earlier than average, “owls” dread this time of year. “Owls only start to feel better later in the day and tend to turn in an hour or two later than average,” says Professor Jim Horne, a director of a sleep research centre.

According to Horne, 15pc of us are larks, 15pc are owls and the remaining 70pc are neither one nor the other. There are advantages to being an evening person, with studies suggesting they tend to have a better sense of humour, but there are considerable downsides. Starting most days unwillingly is not fun, especially in winter. Nor is being assumed to be lazy.

When it comes to business success, morning people have the upper hand, not least because they're in sync with the corporate schedule. But owls can retrain themselves.

Root causes

Each of us has a circadian rhythm which peaks and troughs at certain times of the day. “There are around a dozen genes involved in the ticking of this clock,” says Simon Archer, a reader in chronobiology.

“A morning or evening preference is 50pc inherited. One gene, Period3, is significant as we've found that people with a long version are more likely to be morning types and those with the short version are likely to be evening types.”

Age is another contributory factor, with children likely to be larkish, turning owlish in adolescence, which peaks in their early 20s, he says.

“Then we become more morning types as we age. When old people wake early, they find it difficult to get back to sleep.”

Get up and go

Set your wake-up time and stick to it. If you sleep more than 90 minutes later at the weekend, you'll inadvertently readjust your body clock to the later wake-up time just in time for Monday morning.

Lose the snooze button too, says researcher Jason Ellis. “You are better off setting the alarm for the time you really have to get up. Jump straight into the shower to regulate the bodily system.”

If you can, fit in a workout, he adds. It starts to speed your metabolism up, leaving you feeling fresher by pumping oxygen to the brain. He advocates swimming or yoga. Gyms often offer personal training and group fitness for early birds, too.

Seek out sunlight

Circadian rhythms are influenced by light exposure, which adjusts your body clock and suppresses the release of melatonin, a natural hormone that tells your body it's time to sleep.

“Immediately after waking, expose yourself to bright light for at least 20 minutes — walking or exercising outside or having bright lights on while you eat breakfast,” says Professor Adrian Williams, who specialises in identifying sleep patterns.

Eat breakfast

“A lot of people who say they aren't morning people are simply people who skip breakfast and therefore feel more and more tired until lunchtime,” says Sara Stanner, a nutritionist.

Our bodies use up glucose in the night and, within two hours of getting up, that glucose needs restoring. Opt for slow-releasing carbs — ideally mixed with protein and fibre. Egg or beans on toast is good, as is oatmeal porridge with nuts and seeds. “I'd recommend cereal, too,” adds Stanner, “especially with added vitamins and minerals, notably folic acid and iron for women, because low levels of these can make them especially tired.

“Don’t go for anything too sugary, which will give you an instant but short-lived energy boost. Your blood sugar will drop as quickly as it rose, leaving you more desperate than ever to be back in bed.”

Don't forget a drink, she adds. “If you're dehydrated, you'll feel lethargic.”

Go to bed an hour earlier

Duration of sleep is less related to morning alertness than you might expect. But the timing of the sleep is important. By going to bed an hour earlier, you could help shift your daily cycle. Also, going to bed and getting up at the same time programmes your body to sleep better — and the higher the quality of sleep, the less groggy you're likely to feel in the morning.

Adapt your environment — so no TVs or computers. Avoid alcohol, caffeine, bright lights and exercise for at least a few hours before bedtime.

Consider Melatonin

In the US, a synthetic version of melatonin is available. It's not licensed here, but you can buy it on the internet. Don't, says Ellis — you can't be sure what you're getting. If you think you need it, see a sleep clinic.

A safer alternative, he says, is foods that are naturally high in melatonin: “Try a cherry juice and a handful of nuts. Also consider foods containing tryptophan, which help stimulate the production of melatonin.

These include eggs, cereal, bananas and turkey. ”We now know we have little clocks in our lungs, liver and pancreas — all areas relating to food. So you can change some of your clock's timings by changing what you eat and when you eat it.”