What is 'quality sleep' and to know you've had it

When thinking about how much sleep you need, it’s common for us to make it a numbers game and only consider getting the recommended seven to eight hours each night. However, if we want to receive all of the benefits that sleep has to offer, our focus should also be on the quality of our sleep.

This is because good-quality sleep offers improvements in our physical and mental health, whereas low-quality sleep works the opposite way. So, after we’ve awoken from our time in bed, how do we actually recognise and measure if the sleep we’ve just had has been of good quality?

That’s where we come in to help. We’ve put together this guide to sleep quality and explained how you can tell if you’ve had a good quality sleep. We’ve also explained how you can measure your sleeping quality throughout the waking day.

What is quality sleep?

When you hear about quality sleep, it refers to the kind of sleep that truly recharges your body and mind. It's the type of sleep that leaves you feeling refreshed and ready to conquer the day. When you're getting quality sleep, you go through all the necessary stages of sleep, like deep sleep and REM sleep, which help with physical recovery and mental sharpness.

You also have a lack of interruptions in your sleep and good sleep efficiency (see below). There are many more ways you can work out if you’ve had quality sleep, and it’s important to do so because quality sleep supports your brainpower, memory, immune system, mood, and overall vitality.

Quality sleep is basically the secret ingredient for a healthy and high-performance life. On the other hand, low-quality sleep carries several risks, such as lower mood, slower recovery, weight gain and hormone disruption.

How to measure if your sleep was good quality

One of the most common ways to work out if you’re having a good quality sleep is by working out your sleep efficiency. This is done by considering three key factors of our sleep, which are then used as a baseline to see how efficiently we have slept. Once we work out our sleep efficiency, we can see how long we were truly asleep and if this is above or below the recommended seven to eight hours.

Knowing this number can help us recognise if we need to maintain or improve our sleeping quality. Here are the three factors for working out sleep efficiency:

• Sleep latency: This measures how quickly you fall asleep. If you doze off within 30 minutes or less after getting into bed, it suggests you're experiencing good sleep quality.
• Sleep waking: This factor tracks how often you wake up during the night. Frequent awakenings can disrupt your sleep cycle and lower your sleep quality. Ideally, you should wake up only once or not at all for a good night's sleep.
• Wakefulness: This refers to the amount of time you spend awake during the night after initially falling asleep. People with good sleep quality spend 20 minutes or less awake during the night.

Using these, we can work out our sleep efficiency, which measures the percentage of time you spend actually sleeping while in bed. Here's a simple way to do it:

1. Determine your actual sleeping duration. Do this by subtracting the time it took you to fall asleep (in minutes) and the time you spent awake during the night (also in minutes) from your total time in bed (again, in minutes).
2. Divide your actual sleep time by your total time in bed (in minutes).
3. Multiply the result by 100 to get your sleep efficiency percentage.

For example: Let's say you spent 480 minutes in bed, took 30 minutes to fall asleep, and had no wakeful periods during the night. Your actual sleep time would be 450 minutes. 450/480 = 0.9375. 0.9375 x 100 = 93.75% sleep efficiency.

Now you can assess the efficiency of your sleep. Anything from 85% or above is a signal of good quality sleep. If you are under this, it needs improvement. By keeping track of your sleep efficiency, you can tell whether your sleep is improving or getting worse.

Seven signs of quality sleep

We know how to measure our sleep efficiency, but this isn’t the only way to tell if you're having a good quality sleep. There are several other indicators that can help you recognise this. If you don’t relate to many of them, think about improving your sleep quality and check out our guide on ways to improve your sleep quality.

Here are seven signs that you're having quality sleep:

1. You feel refreshed

One of the most obvious signs of a good night's sleep is waking up feeling refreshed and energised. If you feel well-rested and ready to tackle the day, it's a good indication that you had quality sleep.

2. Consistent sleeping hours

Another easy way to recognise quality sleep is if you are maintaining a consistent sleep duration. If you're able to regularly sleep for the recommended seven to nine hours (for adults) without waking up frequently during the night, it suggests that you're getting a good quality of sleep.

3. Falling asleep quickly

Falling asleep within a reasonable amount of time after getting into bed indicates good sleep quality. If you struggle to fall asleep and spend a long time tossing and turning, it may be a sign of poor sleep. If you find you’re often struggling to fall asleep, then try a few sleeping techniques, which you can find in our guide on what to do when you can’t sleep.

4. Minimal wake-ups during the night

While it's normal to wake up briefly during the night, frequently arising can disrupt its quality. If you're able to sleep through the night with minimal interruptions and quickly fall back asleep after waking up, it suggests you’re getting a better quality of sleep.

5. Feeling rested without the need for napping

Quality sleep should leave you feeling rested throughout the day without the urge to take frequent naps. If you can maintain alertness and productivity without relying on daytime naps, it's an indication of a good night's sleep. The logic applies to caffeine or other stimulants; if you need several coffees to stay awake, then you might not be getting a good quality of sleep. If you regularly get tired during the day, see our guide on tackling tiredness.

6. Dreams and REM sleep

Rapid Eye Movement (REM) sleep is a stage of sleep associated with vivid dreaming. Experiencing regular dreams and being able to recall them is a good indicator that you're spending enough time in the REM stage, which is important for overall sleep quality.

7. Feeling emotionally balanced

A good night's sleep contributes to emotional well-being. If you wake up feeling emotionally stable, with improved mood and reduced irritability or anxiety, it suggests that your sleep quality has been sufficient.

Best products for helping you get a quality sleep

To help you improve your sleep quality, we’ve picked out some of the best sleep-aiding products. They can help to improve and track the quality of your sleep regardless of how good it already is. Here they are:

• Fitbit Inspire 2 Health & Fitness Tracker, Amazon, £44: Fitbit’s Inspire 2 is a great basic tracker for anyone on a tight budget. It has heart rate monitoring capabilities and sleep tracking so that you can review and evaluate your sleep. It also tells you the quality of your sleep and how many times you woke up. Check out our guide to the best fitness trackers for more sleep-tracking devices.
• Simba Orbit Weighted Blanket, £169, Simba: Designed to help you drift off and stay there, the Simba Orbit Weighted blanket is made with nano-bead technology and breathable fabrics. With a 100% cotton machine washable cover, this weighted blanket aims to keep you cool and comforted all night long. For more information on weighted blankets, check out our guide to the best weighted blankets to help you sleep and relax, as recommended by sound sleepers.
• Magicteam Sleep Sound White Noise Machine, Amazon, £19.99: This portable, adaptable white noise machine offers 40 different sounds, 32 volume level options and three timer settings. White noise has long been used as an aid to sleep, with studies showing it has the ability to help people fall asleep up to 38% faster. Check out our guide to the best white noise machines for more choices and information.
• Drowsy Silk Sleep Mask, Amazon, £69.99: Improve sleep quality with this ultra-chic yet functional eye mask made from 100% pure mulberry silk. Its wide design will block out external light, with cushioning for maximum comfort. Hypoallergenic, chemical free and with a soothing touch, this eye mask provides a simple solution to a more restful night’s sleep. Check out our guide to the best eye masks for more choices and info.

If you want more expert tips and recommendations, check out our page on sleep, which includes guides on breathing exercises for better sleep, the best eye masks for sleeping, the best white noise machines and the best bed sheets, according to experts.