Thursday, March 19
Fatigue is something everyone experiences at some point.
A hard workout.
A long day.
A late night.
But if you’re living without a thyroid, fatigue can feel… different.
Not just “tired.”
Heavier. Slower. Harder to push through.
And for a long time, I didn’t fully understand why.
What Makes Thyroid-Related Fatigue Different?
The thyroid plays a major role in how your body produces and uses energy.
Thyroid hormones — T3 and T4 — help regulate metabolism at the cellular level. That means they influence how your cells create energy to power everything you do.
Research published in journals such as The Journal of Clinical Endocrinology & Metabolism shows that when thyroid hormone levels are low or not optimized, the body’s energy production can slow down.
This doesn’t just affect physical energy.
It can also affect:
• Mental clarity even if we don't want to believe it this is so true and I hate it!
• Muscle function - Weight training has defiantly helped me with this
• Recovery- I take longer to recover then others
• Overall endurance- I always look at this as it's just in my head
So instead of just feeling “tired,” fatigue can feel more like your system is running at a lower capacity.
Why Fatigue Can Persist — Even with Medication
For those of us without a thyroid, hormone levels are replaced through medication like T4 and sometimes T3.
These medications are essential, but they don’t always perfectly replicate the body’s natural hormone rhythm.
Studies have shown that some individuals continue to experience fatigue even when their lab values fall within a “normal” range.
That can be frustrating.
Because on paper, everything looks fine.
But in real life, your body may feel different.
What Fatigue Looks Like for Me
Over the years, I’ve learned to recognize a different kind of fatigue.
Not just muscle soreness from training.
But a deeper fatigue that can show up as:
• Low energy even after rest/that's why I never take naps
• Slower recovery between workouts/lots of walking helps me with this
• Mental fog or lack of focus/ write everything down
• Days where everything feels harder than it should, even after I have been doing things the same for years.
And when you’re training for endurance races, that matters.
Because endurance training already asks a lot from your body.
What I’ve Learned Through Endurance Training
Endurance sports have taught me how to work with fatigue instead of fighting it.
That means:
• Listening to my body more closely
• Adjusting workouts when needed
• Prioritizing recovery just as much as training
• Fueling properly — not under-eating
• Being patient when energy feels low
Some days are strong.
Some days are slower.
But both are part of the process.
What the Research and Real Life Both Show
Fatigue without a thyroid isn’t just in your head.
It’s connected to how your body regulates energy at a deeper level.
But here’s the important part:
"It doesn’t mean you can’t train. It doesn’t mean you can’t improve.
And it doesn’t mean you have to stop."
It means you have to learn your body.
The Takeaway
If you’re feeling this kind of fatigue, you’re not alone.
Your body isn’t broken.
It’s operating differently.
And the more you learn to understand it, the better you can adapt your training, your recovery, and your expectations.
Because endurance — in sport and in life — isn’t about never feeling tired.
It’s about continuing to move forward anyway.
And remembering:
"A small step still takes you forward."
Just keep going!
#NoThyroidAthlete
#IronSunshine
#EnduranceAthlete
#ThyroidWarrior
#StrongOver50






