Can you sleep too much? Why a long sleep can still leave you tired

It's a very relatable weekend story. You finally get a chance to sleep in, you stay in bed for ten hours or more, and you wake up feeling worse than you did on a weekday. This weekend, posts about exactly that trended online: people describing sleeping for 10, 12, even 15 hours and still waking up groggy, then dragging themselves into a sleepy Monday.

So can you sleep too much? And why does a long sleep sometimes leave you more tired, not less?

Here is what counts as a long sleep, why a big lie-in can feel rough, and how the Thrive Health Band helps you find the amount and timing of sleep that suits you.

How much sleep do adults need?

The Sleep Health Foundation says sleep needs settle in early adult life, at around 20, and that most adults need between 7 and 9 hours a night to feel refreshed and function at their best the next day. It also says individuals vary. Some people are genuine short sleepers, while others need more than average. Older adults tend to spend more time in bed, but their sleep needs are similar to when they were younger.

So 7 to 9 hours is a guide, not a rule. A good test is how you feel and function during the day. For more detail, see how much sleep adults need by age.

Can you sleep too much?

A long sleep every now and then is usually just your body catching up. After a run of short nights, a big week, travel or being unwell, sleeping longer on the weekend is common, and it's not something to stress about.

What's more useful to notice is the pattern. If you regularly need well over 9 hours and still wake up tired, or you feel sleepy through the day even after long nights, that's worth looking into. The Sleep Health Foundation says ongoing daytime sleepiness can have many causes, from lifestyle and sleep habits to your physical and mental health, and that working it out with your GP is often the best way forward.

Why a long sleep can leave you groggy

There are a few everyday reasons a big sleep can feel worse than a normal one:

Your body clock gets out of step. Sleeping in by two or three hours is a bit like flying a couple of time zones west. It shifts your rhythm, which can make that night's sleep harder and Monday morning rougher. Our article on social jetlag explains this.
Waking from deep sleep. The groggy, heavy feeling right after waking is called sleep inertia. It can feel stronger when you wake at an unusual time. See why mornings can feel foggy.
Time in bed isn't the same as time asleep. Ten hours in bed with lots of tossing and turning can add up to less restful sleep than it seems.
It might be a catch-up. A very long sleep is often a sign you've been running short during the week. The lie-in isn't the problem; the short nights before it are.

Small ways to get more from your sleep

Keep your wake time steady. Try to get up within about an hour of your usual time, even on weekends.
Go to bed a little earlier instead. If you're tired on Saturday, an earlier night usually works better than a much later morning.
Get morning light. Ten to twenty minutes outside soon after waking helps set your body clock for the day.
Nap short, not long. If you need a top-up, a nap of under 20 minutes, earlier in the afternoon, is less likely to leave you foggy. Our naps and nights article has more.
Protect your weeknights. A regular wind-down and a consistent bedtime during the week mean less to catch up on later.

How Thrive helps you find your sweet spot

The Band has no screen, so there's nothing glowing on your wrist at night. Wear it to bed, and the Thrive by Optihealth app shows how long and how well you slept, alongside how you feel the next day.

Sleep detail. See your time asleep and your sleep window each night, plus week and month views, so you can spot long catch-up sleeps after short weeks.
Sleep scores. Thrive scores four parts of your sleep: how much, how well, how regular and how well timed. The amount score is highest between 7 and 9 hours and dips gently beyond 9, and the regularity score shows how much your bed and wake times move around.
Tonight's focus. Each night Thrive suggests three simple actions, such as keeping a fixed wake time or choosing a bedtime window, based on what will help most.
Bedtime reminder. Set a reminder so winding down happens at a steady time.
Today's Vitality and recovery insights. Sleep & Recovery feeds into your daily view, and Thrive's recovery insights can estimate how long until you're back to your usual.
Check-ins and Ask Thrive. Log your energy and mood each day, then try asking "Do I feel better after 8 hours or 10?" or "How did I feel after my lie-ins this month?"

Thrive also learns what is usual for you across nine areas of your health, from what the Band measures and what you log, and keeps track right across your health, including heart, HRV, temperature, stress and mood, meals and Food Fit, blood tests, medications and supplements and your medical history.

If you'd like support, Thrive Loops lets you share selected information with a participating trainer, health professional or someone you trust. You decide what to share and with whom, and you can change or revoke access at any time.

When to talk to your GP

A long sleep after a big week is normal. But if you regularly sleep much longer than 9 hours and still feel tired, you're nodding off during the day, a bed partner notices loud snoring or pauses in your breathing, or you feel low or flat for more than a couple of weeks, talk to your GP. Take extra care if you feel sleepy when driving. Thrive isn't a diagnosis, but Ask Thrive can help you get ready by lining up a few weeks of your sleep, energy and mood, and you can share a Clinician Summary. Here is how to use Ask Thrive before a GP appointment.

Before you buy

You'll need a compatible iPhone or Android phone, because the Thrive app is on the Apple App Store and Google Play, in Australia and eight other countries. The app stores are only for downloading the app, though; they aren't where you buy the Band or a Plan. You can buy at thrivehealthband.com, or at a participating World Gym Australia location or health and wellness clinic.

The Thrive Health Band is A$660 for the first year under the launch offer. That includes the Band, which is yours to keep, and 12 months of the Thrive by Optihealth app, My Health on the web, Health Fingerprint, Ask Thrive, Thrive Loops and your data, paid once upfront. Prices are in AUD and include GST. Free Australia-wide shipping during the launch offer (usually A$14.99).

Nothing renews automatically. After your first year, you can get a new band plus 12 more months for A$660, or keep your band and renew the Thrive Connected Plan for A$240 a year, or A$29 a month with no lock-in.

You're also covered by a 12-month Thrive Care Warranty, and consumer guarantees under Australian Consumer Law always apply. See Returns if something is wrong with your purchase.

Common questions

Is it bad to sleep 10 hours?

Now and then, it's usually your body catching up after short nights or a busy week. If you regularly need 10 hours or more and still feel tired, talk to your GP.

Why am I more tired after sleeping in?

A big lie-in can shift your body clock and leave you waking at an unusual point in your sleep. Keeping your wake time within about an hour of usual can help.

Can Thrive show how much sleep I need?

Thrive shows your sleep each night alongside your energy and mood check-ins, so over time you can see which amount of sleep leaves you feeling your best.

For more answers, see Questions.