Why can you wake up tired… even after sleeping the whole night?
Why can simple tasks feel exhausting… when medical tests show nothing seriously wrong?
Why can you feel physically drained… even if you haven’t done much physical activity?
And why is it that sometimes… the exhaustion may not come from what your body has been doing but from everything your mind has been carrying?
THE STORY
She was tired most days.
Not just tired.
Bone tired.
The type of tired where putting pants on felt like exercise.
She went to bed early.
Stayed in bed longer.
Took vitamins.
Got blood work done.
Everything looked great.
But she still felt tired.
Everyone kept telling her…
“Maybe you just need to work out more.”
“Probably not sleeping enough.”
“You think too much.”
But nobody could see what was going on in her mind.
She woke up and started thinking.
What if she made a mistake at work?
Was her friend mad at her yesterday?
Why did her head hurt?
Did she pay that bill?
What if something happened to her kids?
Her body wasn’t doing much but her mind had prepared for battle all day.
By the time night came… she had nothing left to give.
She looked at herself in the mirror and wondered:
“How can I be this tired when I didn’t do anything today?”
INSIDE THE MIND: WHAT’S HAPPENING UNDERNEATH
Anxiety is more than worried thoughts swirling around your mind.
It can impact your entire body.
When your brain constantly expects bad things to happen, your body keeps preparing you to fight or run.
Your muscles tighten.
You breathe faster or more shallowly.
Your heart pumps harder.
You scan everywhere looking for danger.
When there isn’t any immediate threat… your body stays somewhat alert just in case.
That level of alertness takes energy.
So even if you haven’t been physically running around… inside, your nervous system may have felt as though it had been fighting or fleeing all day.
THE WEARINESS OF CONSTANT ALERTNESS
An anxious mind rarely stops worrying.
It scans.
Analyzes.
Plans.
Broods.
It picks up on small changes in someone’s tone.
Wonders what they really meant.
Thinks about what to say next.
You may mentally go over situations dozens of times a day.
The trouble is that each scenario may not require much brain power.
But add them all up… and your mind is working overtime figuring out what to worry about next.
WHEN YOUR MUSCLES NEVER RELAX
Most of the tension anxiety creates in your body goes unnoticed.
You may not realize your shoulders are up by your ears.
Or that you’ve been clenching your jaw.
Or deepening the grooves between your eyebrows.
You might breathe rapidly or shallowly.
When your muscles remain tense for hours, your body can begin to feel sore, heavy, and exhausted.
That’s why you can feel worn down by the end of the day… despite sitting at your desk.
WHY YOU MAY STILL BE TIRED AFTER SLEEPING
Someone with anxiety may sleep for eight hours and still wake up tired.
It may take them hours to fall asleep because their mind won’t slow down.
They may wake up several times during the night but not remember it.
Have disturbing dreams.
Wake up anxious about their day.
Sure, they spent eight hours in bed.
But their mind and body were up fighting wars all night.
THE CRASH AFTER HOLDING EVERYTHING TOGETHER
During stressful moments, your body releases stress hormones that help you remain alert and keep going.
You keep going.
Fix the problem.
Take care of your kids.
Stuff down how you feel.
Until you finally have time to relax… and then you crash.
You feel heavy.
Unmotivated.
Foggy.
Exhausted.
But that doesn’t mean you became weak after the stress passed.
It could mean your body finally stopped long enough for you to realize how tired you were.
THE TIREDNESS OF OVERANALYZING
Decision-making takes energy.
When you worry a lot, even deciding what to wear can become exhausting.
“What if I make the wrong decision?”
“What will people think?”
“What if I regret this?”
“Should I look at this one more time?”
Instead of deciding and moving forward…
you analyze every possible outcome.
This can lead to decision fatigue.
Problems concentrating.
Forgetfulness.
And a general sense that your brain is fuzzy.
Sometimes anxiety-related fatigue doesn’t come from doing too much.
Sometimes it comes from your mind never deciding that anything is finished.
HOW IT CAN BECOME A CYCLE
When we feel tired, we naturally slow down.
We don’t go to the gym.
Skip hanging out with friends.
Lie in bed more.
Stop doing things that make us tired.
Drink more caffeine to get through the day.
Rest is good.
But too little activity will slowly decrease your physical conditioning.
And ordinary activity will make you feel extra tired.
You notice how exhausted you feel and start thinking:
“Oh God. What if I’m physically sick?”
That triggers anxiety.
Anxiety keeps you up at night, which uses more energy.
And before you know it… you’re in a constant exhaustion-anxiety cycle.
IT ISN’T ALL IN YOUR HEAD
Fatigue caused by anxiety is real.
Your body feels every symptom.
Anxiety should not be presumed to be the cause of your tiredness.
Fatigue can be a symptom of iron deficiency, thyroid problems, sleep apnea, infections, medication side effects, vitamin deficiencies, diabetes, inflammatory diseases, depression, and many other physical health issues.
New, severe, sudden, or worsening fatigue should always receive proper medical evaluation—especially if you experience unexplained weight loss, fever, bleeding, chest pain, shortness of breath, fainting, extreme weakness, or other concerning symptoms.
Just because medical tests don’t reveal a problem… doesn’t mean your tiredness isn’t real.
It could mean it’s time to look elsewhere, such as your sleep habits, stress levels, mood, anxiety, daily activity, and more.
THE SHIFT IN QUESTION
Stop asking yourself:
“Why am I so tired when I didn’t do anything today?”
And start asking yourself:
“What have my mind and body been doing all day?”
How much time did you spend worrying?
How many times did you check your phone for notifications?
Were your muscles tense?
Were you breathing deeply or taking short breaths?
Did you actually sleep, or did your mind race all night?
Sure, you spent eight hours in bed.
But how much rest did your body actually get?
Once you start considering mental exertion as taxing…
you may understand your fatigue a little better.
WHAT YOU CAN DO ABOUT IT
Take a few minutes each day to let your body relax.
Slow your breathing.
Release tension in your jaw and shoulders.
Get your body moving each day, even if it’s a five-minute walk outside.
Cut back on caffeine if it’s affecting your ability to relax or sleep.
Write your worries down.
Stop carrying them in your head all day.
Give yourself a certain amount of time to worry.
When worry returns outside that time, gently redirect your attention to what you are doing.
Go to bed and wake up at consistent times each day.
And remember: it’s okay to ask for help when your anxiety becomes too much to handle on your own.
You don’t have to force yourself not to be tired.
You just have to figure out what might be draining you and start taking steps to lighten your load.
HOLD ON TO THIS
You’re not lazy because anxiety leaves you tired.
You’re not weak because everyday tasks have suddenly become difficult.
Sometimes your body becomes tired from constantly worrying about things that may never happen.
See a doctor to have your physical health assessed.
Focus on improving the quality of your sleep, moving your body more, and finding support for the anxiety itself and your body can learn to relax when there is no genuine threat.
And when your mind gets the green light to rest… your body may begin to feel rested too.
Dr. Jassam is a practicing medical doctor in Canada with additional qualifications and extended training in psychiatry. He holds a postgraduate diploma in psychiatry from the Royal College of Physicians of Ireland and a master’s degree from the University of Melbourne. He is also the author of several books on ADHD, panic disorder, burnout, and other mental health topics. His writing combines medical evidence, psychiatric knowledge, and clinical experience.
