Iron Deficiency in Female Athletes: What to Watch For and How to Fix It
If you're training consistently, eating well, and doing "all the right things" – but still feel exhausted – it might be time to look beyond motivation or recovery. For many female athletes, iron deficiency is the hidden reason performance plateaus, fatigue lingers, and mood dips… even when everything looks perfect on paper.
Let’s break it all down – from the warning signs to testing, fuelling, and how to get back to feeling strong again.
Why Iron Matters – and Why Female Athletes Are High Risk
Iron is responsible for carrying oxygen in the blood – which means it directly affects your endurance, energy levels, recovery, cognition, and immune system.
When you're low on iron, your body simply can’t deliver oxygen efficiently. That’s a big deal for runners, triathletes, and women doing high-volume or high-intensity training.
Here’s why female athletes are more likely to become deficient:
Monthly blood loss from periods
Iron lost through sweat (which increases in hotter climates or longer sessions)
Diets lower in red meat or fully plant-based
Underfuelling or chronically low energy availability
Gut issues that affect absorption (e.g. IBS, coeliac, low stomach acid)
Add endurance training to that mix – and it’s a perfect storm for depletion.
Top Signs Your Iron Might Be Low
Iron deficiency doesn’t always look dramatic at first. It creeps in gradually – and often gets brushed off as stress, age, or just "being a bit run down."
Look out for these common signs:
Heavy legs or struggling through runs that used to feel easy
Feeling breathless or lightheaded – especially on hills or intervals
Constant fatigue that sleep doesn’t fix
Cold hands and feet, or feeling cold when others are fine
Pale skin, brittle nails, or thinning hair
Frequent colds or infections
Brain fog, low mood, anxiety, or loss of motivation
You don’t need to tick all of these boxes – even one or two can be a sign that something’s off.
What to Test – and When
If you’re noticing symptoms, don’t guess. Book a blood test.
Here’s what to ask for:
Serum Ferritin – this measures stored iron
Haemoglobin – indicates red blood cell levels
Transferrin Saturation – shows how well iron is being transported
CRP – checks for inflammation (which can affect test results)
For endurance athletes, a ferritin level under 30 is a red flag. Ideally, we want to see ferritin above 50 – especially if you’re training hard.
👉 Test every 6–12 months, or every 3–6 months if:
You have heavy periods
You’re following a plant-based diet
You’ve had low levels in the past
You’ve recently increased your training load
You’re struggling with fatigue, performance, or mood
What Happens If You Ignore It
This is where things get serious.
Left untreated, low iron can:
Increase your risk of injury, illness, and hormonal imbalance
Slow down your recovery and adaptation to training
Lead to full-blown iron-deficiency anaemia, which can take months to reverse
Cause burnout – physically and mentally
So no – pushing through or “toughing it out” is not the answer. Being proactive here can literally make or break your race season.
Food First: Smart Iron Fuelling
You can absolutely improve iron status through food – especially if you catch it early.
Prioritise iron-rich sources:
Haem iron (well absorbed):
Red meat (beef, lamb, venison)
Liver (small amounts weekly – it’s potent!)
Dark poultry (thighs, not breast)
Non-haem iron (plant-based but less absorbable):
Lentils, chickpeas, beans
Tofu and tempeh
Pumpkin seeds, sunflower seeds, hemp seeds
Oats, quinoa, dark leafy greens (like spinach or kale)
Boost absorption with vitamin C:
Citrus, kiwis, strawberries, tomatoes, peppers – add them to meals for a simple absorption upgrade
Avoid absorption blockers at the wrong time:
Tea, coffee, calcium-rich foods and supplements
Keep these 2 hours away from your iron-rich meals
Extra tips:
Cook in cast iron pans
Soak beans and lentils overnight to reduce phytates
Batch cook iron-rich meals so they’re easy to grab during busy weeks
Should You Supplement?
If blood tests show low ferritin or haemoglobin – and you’re symptomatic – supplements can help. But don’t supplement without testing first.
The most common types:
Ferrous sulfate – effective, but can cause gut upset or constipation
Ferrous bisglycinate – gentler and often better tolerated
Liquid iron (like Spatone) – good for maintenance or mild deficiency
How to take it:
Always with vitamin C (a squeeze of lemon or orange juice works well)
Take on an empty stomach, away from food, caffeine, or calcium
If it upsets your gut – try taking it every other day to start
Don’t mix with your magnesium or calcium supplements
For more serious deficiency – or if you don’t tolerate oral iron – your doctor might recommend an iron infusion. It’s usually quick and effective, but needs to be medically prescribed.
⚠️ Important: More is not better. High-dose iron when you don’t need it can do more harm than good.
Adjusting Training with Low Iron
If your iron is low, your body is already in a stressed state.
Trying to “push through” hard sessions will only delay your recovery – and potentially worsen the issue.
Here’s what to do:
Shift to Zone 2 training, mobility work, or technique drills
Avoid hard intervals, tempo runs, or anything that spikes fatigue
Prioritise sleep, fuelling, hydration, and stress reduction
Track heart rate and mood – both are useful indicators of how you’re responding
Stay consistent with strength work (lower load, high focus on form)
Keep your coach in the loop – so we can adapt your plan smartly, not emotionally
How Periods Impact Iron Levels
This bit is often overlooked – but your period plays a big role in iron loss.
You lose iron during your bleed, so even a typical cycle can affect energy and recovery. If your periods are heavy or longer than 7 days, you’re at even higher risk.
Try this:
Increase iron-rich foods in the days leading up to and during your bleed
Track how heavy your flow really is – using a menstrual cup can help quantify it
Consider iron testing more frequently if your periods are heavy
Some women find a hormonal IUD helps reduce flow and preserve iron levels – speak to your GP if this might be suitable
How to Track Progress and Reassess
Once you start addressing iron deficiency through food, supplements, or both – you should notice changes within 6–8 weeks.
Signs you’re on the right track:
More energy during the day
Better mood and motivation
Runs start feeling easier again
Improved sleep and recovery
Less breathlessness during efforts
📌 Don’t forget to retest after 2–3 months to check progress – and ensure your protocol is working.
If symptoms persist despite good nutrition and supplementation, it might be time to dig deeper with a GP, sports dietitian, or specialist blood panels.
Key Takeaways
Iron is crucial for performance, energy, and recovery
Female athletes are especially vulnerable – due to periods, training, diet, and underfuelling
Don’t guess – test your iron status regularly
Fuel smart with iron-rich foods, vitamin C, and absorption strategies
Supplement wisely – only when bloodwork confirms it’s needed
Train with compassion – and adapt sessions while you recover
Track your cycle – and understand how periods affect your iron status
You don’t have to feel tired all the time. If something feels off, trust your gut – and take action.
At Pretty Strong Coaching, we’re here to support your training, your nutrition, and your health – not just your workouts. Because peak performance starts with feeling good in your body, not dragging it through every session.
Feeling constantly tired – even when you’re training smart and eating well?
You don’t have to guess your way through fatigue, low motivation, or performance plateaus.
At Pretty Strong Coaching, we help busy women get their energy and confidence back – through tailored training, smart nutrition, and coaching that actually works with your hormones, cycle, and lifestyle.
If you're wondering whether iron deficiency is part of your story – or you're just tired of feeling tired – book a free 15-minute chat with me and let’s figure it out together.
RELATED POSTS
