If You’re a Woman Training Fasted, Stop Now: What Happens & What to Do Instead

A Personal Note

I used to train fasted, thinking it was helping me lean out and build resilience. I ignored hunger cues and pushed through fatigue because that’s what the mainstream fitness world told me to do.

Then I discovered Dr. Stacy Sims — and everything changed.

“Women are not small men. Stop eating and training like one.”
— Dr. Stacy Sims

Her book is literally called ROAR, and it taught me something that no coach, fitness plan, or challenge ever had:
Women are not small men.
We have different hormones, different cycles, and different needs — and when we train in alignment with that, we thrive.

This blog is the guide I wish I had when I started training. If you’re training fasted, here’s what you need to know — backed by real science, made for real women.

Why Women Shouldn’t Train Fasted

You’ve probably heard that fasted workouts burn more fat. What they don’t tell you is that this research was done on men — who don’t cycle through complex hormonal shifts every month.

Here’s what happens to your body when you train fasted:

↑ Cortisol (stress hormone): Women are more sensitive to cortisol. Too much leads to belly fat storage, disrupted sleep, and fatigue.
↓ Estrogen & Progesterone: Fasting can suppress reproductive hormones, impacting your cycle, mood, and long-term health.
Menstrual Disruption: Chronic fasted training can lead to irregular or missing periods (amenorrhea) — a red flag your body is under too much stress.
Muscle Breakdown: Without fuel, your body may burn muscle instead of fat — especially during high-intensity sessions like Muay Thai.

Dr. Stacy Sims says: “Women should never train fasted. Period.”

Her work is rooted in female-specific physiology and backed by over 20 years of research.

Stop believing these myths:

Myth: Fasted workouts help women lose fat faster.
Truth: Fasted workouts can increase fat storage by raising cortisol and suppressing metabolism in women.

Myth: If I eat before training, I’ll feel sluggish.
Truth: The right fuel actually helps you train harder, recover better, and build lean muscle.

Where the Science Comes From

Most early exercise science excluded women due to hormonal complexity. Researchers like Dr. Stacy Sims, Renee McGregor, and Louise Burke are changing that.

Their work is based on:

Female-focused studies
Elite athlete data
Real-world application across menstrual, perimenopausal, and postmenopausal stages

What About Hunger Cues?

If you feel hungry before training — that’s not a flaw in your discipline.
That’s your body working correctly.

Hunger = a signal to fuel performance, protect muscle, and stabilize hormones.

What to Eat Before Training (Without Overthinking It)

You don’t need a full breakfast. You need a light snack with carbs + protein 30–60 mins before your session.

Quick Pre-Workout Options:

Banana with almond or peanut butter
Rice cake with tahini or nut butter
Protein smoothie with berries and oats
Dates + a handful of almonds
Overnight oats with chia and maple syrup

These help stabilise blood sugar, improve output, and reduce the hormonal stress response from intense training.

What to Eat After Training (And When)

You’ve trained hard — now your body needs nutrients to recover and adapt.

Eat within 30–45 minutes

This is your recovery window. Fueling here:

Rebuilds muscle
Lowers cortisol
Replenishes glycogen stores
Reduces next-day soreness and fatigue

Post-Workout Meal Ideas:

Smoothie with banana, oats, protein powder, and plant milk
Tofu stir-fry with rice and veggies
Wholegrain toast with avocado and hemp seeds
Yogurt (dairy or non-dairy) with berries and granola

You don’t need perfection. Just nourishment. That’s how your body learns to trust you again.

How This Applies to Women in Muay Thai

Muay Thai isn’t gentle.
It’s dynamic, powerful, and taxing — and it demands fuel.

If you’re sparring, hitting pads, or doing circuits without eating, you’re setting yourself up for:

Poor performance
Hormonal burnout
Low energy and inconsistent results

At Roar MMA Fitness on the Sunshine Coast, we support women in learning to train with their bodies, not against them.

Want to Go Even Deeper?

Resources I Recommend:

ROAR by Dr. Stacy Sims
The Proof Is in the Plants by Simon Hill
The Proof Podcast with Simon Hill – often features hormone, recovery, and performance science
Dr. Stacy Sims on Why Women Shouldn’t Train Fasted

Ready to Train Smarter?

Join Roar MMA Fitness, where we help women build strength, resilience, and confidence — with a training and nutrition approach that honours your body.

Explore Our Classes

Contact Roar MMA Sunshine Coast

References & Citations:

Sims, S. (2016). ROAR: How to Match Your Food and Fitness to Your Female Physiology for Optimum Performance, Great Health, and a Strong, Lean Body for Life.
Burke, L. (Australian Institute of Sport). Nutrition for Female Athletes Guidelines
McGregor, R. (2020). More Fuel You: Nutrition for Performance, Energy, and Hormonal Balance
Dr. Stacy Sims – YouTube Channel
Simon Hill – The Proof Podcast