We are all familiar with that feeling during the first 15-minutes after waking up in the morning. Our eyes are crusty, our breath stinks, our hair is a mess, and we feel grumpy and sluggish. Waking up in the morning is always hard. You sit up in bed but you’re still actually asleep, and all you want to do is roll over and hit the snooze button. Waking up in the morning becomes even harder in winter when it’s all warm and cozy in bed, and the thought of getting out of it is not so appealing. Even putting toothpaste on your toothbrush can seem complicated when you are half asleep.

This grogginess that most of us experience in the first moments after waking up in the morning is called sleep inertia. This is a transitional stage between sleep and wakefulness when parts of your brain are still asleep while the body is trying to wake up. All of us experience morning grogginess, but now we know it also has a name and can be worse than being drunk. That’s right, during morning grogginess the brain is as inactive as when drunk. Therefore, if you try to drive right after getting out of bed, you can actually end up in a crash.

What Is Sleep Inertia?

It’s all in the brain. Going to sleep or waking up, feeling fresh or groggy – it’s all in the brain. No matter how long or well you sleep at night, when you wake up in the morning, you’re almost always likely to feel tired for the first few minutes. Most people think that getting enough sleep at night can help them avoid morning grogginess. But the unfortunate truth is that morning grogginess has no connection to how long or how well you sleep at night. In fact, the deeper your sleep, the worse the sleep inertia.

Sleep has four stages. The first three stages are non-REM stage sleep while the final stage is REM sleep when dreams occur. During the first stage of sleep, the brain is still active, and it’s easy to wake up from that stage. During the second stage, it is slightly harder to wake up, but there is no grogginess even if you wake up from that stage. But during the third and fourth stages of sleep, the brain is completely inactive, and it is harder to wake up. When a person is in deep sleep it takes them some time to realize that someone is trying to wake them up. It takes even longer to wake up and start comprehending things.

Sleep inertia occurs because parts of the brain takes time to fully you wake up even after the person is awake. This is also the reason why we keep yawning till an hour after we wake up. The mechanism behind this is not very complicated. The part of the brain that’s responsible for our physical functioning is called the brainstem arousal system, and the part of the brain that controls our thinking, decision-making, and self-control is called the prefrontal cortex.

The brainstem arousal system becomes active the moment you wake up. But the prefrontal cortex takes some time to become active and alert. Until the prefrontal cortex becomes active, we feel tired, groggy, and keep yawning.

Why the Delay?

You could well ask why the prefrontal cortex takes time to become active when the rest of the brain becomes active the moment a person wakes up. This is because of melatonin, the sleep hormone. The brain rests when we sleep because of melatonin production. When it’s time to wake up, the melatonin levels slowly start to diminish. This helps some parts of the brain to wake up immediately. But the remaining levels of melatonin continue to affect other parts of the brain until they are completely diminished.

Sleep inertia is worse in two cases: when we oversleep and when we get insufficient sleep. To reduce the impact and duration of sleep inertia, we must not only get sufficient sleep but also try to wake up at the end of a sleep cycle instead of in the middle of one.

Overcoming Sleep Inertia

In most cases sleep inertia is normal. There are parts of the brain that take time to wake up completely, and that is not unusual. But in some cases, sleep, inertia can last longer than usual. When sleep inertia lasts for few hours after waking up, we feel sluggish and cannot focus or concentrate.

However, there are steps we can take to minimize the effects of sleep inertia. The following are some of the ways to overcome morning grogginess and feel fresh and alert.

Get Sufficient Sleep: Getting proper sleep is one of the most important factors behind minimizing the impact of sleep inertia. When we fail to get sufficient to sleep at night the melatonin produced in the brain takes a long time to diminish. The longer the melatonin remains in the brain, the worse the sleep inertia.
Avoid Oversleeping: Have you noticed that you feel groggier when you sleep longer than usual? This happens when you wake up in the middle of a sleep cycle instead of at the end of one. Our sleep inertia is more significant when we wake up in the middle of the REM stage. Therefore, to avoid feeling groggy in the morning be careful not to oversleep. Going to bed and waking up at the same time every day reduces the impact of sleep inertia.
Avoid Caffeine and Alcohol Before Bed: Caffeine and alcohol are known to block the neurotransmitters responsible for melatonin production. Avoiding these close to bedtime can help you get sufficient sleep and minimize morning grogginess.
Maintain a Sleep Routine: Preparing to go to bed by staying away from backlit devices, vigorous activities, and heavy meals can bring on sleep more easily and help you get your full quota of sleep. This reduces sleep inertia.

Sleep quality depends on several factors, waking up the right way and feeling refreshed is one of them.