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Centr Team

Fatigued vs tired: the difference matters for sleep

Centr Team

You felt exhausted. You went to bed. But now you’re lying there, finding it impossible to fall asleep…

It’s possible you’ve encountered the difference between feeling fatigued and feeling tired.

While these terms are often used interchangeably, they are not the same thing, and knowing the difference could make a big difference to your overall sleep quality.

Let’s find out which one actually means it’s time to go to bed.

What is fatigue?

Fatigue is what many of us feel at the end of a tough week – as if exhaustion has been adding up with each passing day. You may experience it physically or mentally, or as a combination of both.

Researcher Dr Karin Olson from the University of Alberta called it “a marker that the body is not able to keep up”.

Signs of fatigue include:

  • Lack of motivation

  • Struggling to concentrate or think clearly

  • Poor short-term memory

  • Physical weakness

What is tiredness?

Tiredness or sleepiness is your cue to go to bed. This feeling is driven by the neurotransmitter adenosine – the longer you’re awake, the more it accumulates, steering your body toward sleep. While activities such as intense exercise or highly-focused work can increase tiredness, you’ll feel refreshed after a good night’s sleep.

Signs of sleepiness include:

  • Yawning

  • Itchy or heavy eyes

  • Drifting off

  • Blurry vision

  • Feeling physically ‘heavy’

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The big takeaway here is that fatigue is not the same as sleepiness, and it’s important that you’re able to spot the difference.

If you are fatigued, get some rest. This may include cutting back on activities, opting for gentle exercise over high-intensity training (think walking vs HIIT), finding a restorative hobby, or taking a day off work. If your fatigue is chronic or getting in the way of daily activities, it may be a symptom of a larger issue, so talk to your doctor.

When you are nodding off, get some sleep. By making sure you only go to bed when you are genuinely tired, you increase the likelihood that you will actually sleep – instead of lying in bed, tossing and turning, feeling frustrated or and anxious about not sleeping.

Disclaimer: This content is not intended as a substitute for medical treatment. If you have experienced sleep issues for three months or more, are facing excessive drowsiness that causes safety concerns, frequently snore loudly, or have been observed having difficulty breathing during sleep, please seek qualified medical advice. For a list of registered healthcare providers worldwide specializing in behavioral sleep medicine, please visit The Society of Behavioral Sleep Medicine.

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