'You can’t just easily stop in the middle of a roller coaster – and the same goes for your sleep': A doctor explains why I'm still exhausted after 8 hours of sleep and the simple way to fix it

January’s here, and for me it’s brought exhaustion, anxiety and an insatiable need to stay in bed. Happy New Year, right? Now, it’s not all doom and gloom and I am exaggerating (ish) but since January 1st, I feel as if I’m constantly trying to wake up.

My alarm goes off and despite sleeping for at least eight hours and keeping a consistent sleep schedule, I'm still unbelievably groggy. If left to my own devices, I'd probably settle in for another few hours of kip.

And I know I’m not alone. Friends, family and colleagues are experiencing the same thing.

So what’s going on?

I spoke to Dr. Lindsay Browning, founder of the Trouble Sleeping sleep clinic, to find out why I feel never fully awake, and how to start January energized so I don't quit on my New Year's resolutions.

What’s behind my grogginess?

I had a fantastic conversation with Dr. Lindsay Browning who, after listening to my complaints, ran through a comprehensive list of what could be behind my long-lasting sleep inertia (the scientific term for feeling groggy in the mornings).

Here are her thoughts...

I was interrupting a sleep cycle

Every night we cycle through different stages of sleep. This includes light sleep, REM and deep sleep.

Dr Lindsay, who has a doctorate in insomnia from the University of Oxford, says: “Approximately every hour and a half we go through light sleep, deep sleep and back through light sleep and have a little bit of REM sleep.

“With each increasing sleep cycle, we get less deep sleep and more REM sleep,” she adds.

So while most of our deep sleep occurs early in the night, you’ll still experience some before waking in the morning.

If left to wake naturally (without a blaring alarm at 6am), our bodies will transition through light sleep before gradually rousing. If you wake feeling refreshed and ready to go, then it’s likely this has happened.

However, Dr. Browning suggests the reason I’m finding it impossible to get out of bed is because my alarm goes off during a deeper stage of sleep. That means my brain is jolted awake before it's ready.

“If you are woken up from the deepest part of sleep… you’ll feel really groggy,” says the neuroscientist.

“It’s because you have a thing called sleep inertia, and this is because your body wants you to finish the full sleep cycle.”

Dr. Browning likens it to a theme park ride. “When you’re on a roller coaster and you’re at the bottom of a roller coaster you’ve got loads of inertia that’s going to pull you up to the next dip,” she says.

“You can’t just easily stop in the middle of a roller coaster because you’ve got momentum — and the same thing goes for your sleep.”

Seasonal Affective Disorder

However, Dr. Browning explains that usually this sleep inertia “disappears within around 15-20 minutes”, so my complaint of feeling exhausted until midday seems a little extreme.

When I told her I worked from home and today was the first time I'd left the house in daylight for a while, the penny dropped.

“Seasonal affective disorder is the winter blues, where people feel more sluggish and they feel down and they don’t have as much energy because they aren’t getting as much bright light exposure,” she explains.

When you first wake-up melatonin, the sleepy hormone, is lingering in your body. But daylight acts as a natural suppressant.

“If in the morning, you’re not going outside and you’re getting lots of darkness, it could be that some of the grogginess you’re feeling... is partly because you haven’t suppressed that melatonin,” Dr. Browning says.

Which is why people who don’t commute to an office or have a job outdoors might be struggling with fatigue throughout the day. Especially when the sun sets before you've finished your shift.

Sleep apnea

Next up Dr. Browning asked if I snored. Sheepishly, I admitted my husband had complained recently that my snoring has been keeping him up.

While snoring is often harmless, it can indicate a sleep apnea disorder which can greatly reduce the quality of your sleep, leading to daytime fatigue.

“If your airways start to become partially blocked that’s what causes snoring. And then if it completely blocks you’ll stop snoring and you might stop breathing, too,” Dr. Browning explains.

“You’ll be silent and not breathing for a minute and then your body will go ‘oh gosh we’ve not got any oxygen…we need to wake up, take a big gasp of breath and then go back to sleep again.’”

These brief moments where breath stops are called apneas and are one of the main symptoms of sleep apnea.

“These apneas can happen hundreds of times in the night and if this is happening it can cause massive fatigue because your sleep is so fragmented it’s rubbish quality sleep.”

Underlying health issues

The last reason Dr Browning gave was underlying health issues. “You might want to speak to your doctor about getting a blood test to see if there’s anything going on,” she says.

Increased lethargy and fatigue throughout the day, even after what seems like a good night's sleep, can indicate deficiencies or imbalances in your body.

“It could be an iron deficiency or a thyroid issue,” explains Dr Browning.

The diagnosis

Recent blood tests have given me the all clear so I can rule out underlying health issues.

And when I asked my husband if I ever stopped breathing in the night, he said no — and I don’t have other risk factors for sleep apnea (like being overweight or smoking) — so I’ve ruled that out, too.

The points that rang most true were a combination of lacking natural daylight in the mornings and interrupting my sleep cycle.

While I was probably experiencing some sleep inertia from my alarm disrupting a deep sleep stage, the groggy feeling persisted well into the day because I hadn’t had any natural daylight to suppress the melatonin that was lingering for my night's sleep.

The solution

Thankfully, it’s an easy solution.

“If you were to deliberately go outside in the morning soon after waking you’d get a lot more natural daylight exposure,” Dr. Browning says. And she notes that even if it’s grey and miserable, “you still get a good amount of physical natural light”.

“This helps to tell your brain it’s the middle of the day and we should be awake, helps you feel more alert and helps you suppress melatonin.”

Dr. Browning also advised that a sunrise alarm clock might be a good solution to help me gradually wake in the morning, instead of abruptly.

“Even with your eyes closed, you can sense light through your eyelids, so those light boxes kind of help to pull you into a lighter part of sleep, getting you into a better place to wake up,” she explains. “They’re really great…I would tell everyone to have one.”

So, adding one of the best sunrise alarm clocks to my morning routine should help is now on my to-do list. Luckily, I already have the Lumie Bodyclock Shine 300 — now I just need to convince my husband of the benefits!

However, the doctor does note that these alarm clocks are often expensive, and “the reality is you can just physically open your front door and go outside.”

My New Year’s resolution is to have my morning coffee in my garden, no matter the weather. I’m sure the fresh air will do me good, too.