Should Women Do Fasted Cardio?

What the science says—and what actually works.

Fasted cardio is one of those fitness buzzwords that refuses to die. You’ve probably heard the claims:

“Burn more fat!”“Train your body to use stored energy!”“Hack your metabolism!”

But when it comes to women—especially those in their 30s, 40s, 50s, and beyond—the question isn’t just “Does it work?”It’s “Is it smart?”

Let’s unpack what the research says, what the real-world results show, and whether fasted cardio fits your goals.

First: What Is Fasted Cardio, Really?

Fasted cardio means doing aerobic exercise (like running, walking, or cycling) in a fasted state—typically first thing in the morning before eating.

The idea is that with low glycogen (carb) stores, your body will burn more fat as fuel.But burning fat during a workout isn’t the same as losing body fat overall. (We’ll get to that.)

What the Research Says

Yes, fasted cardio can increase fat oxidation during the workout. But when total daily calorie balance is the same, fasted vs. fed cardio doesn’t lead to more fat loss over time.

In fact, multiple studies show that body composition changes (fat loss, muscle retention) come down to total energy balance and consistency—not when you eat.

So while you might burn more fat during the workout, that doesn't necessarily mean you'll burn more fat in the long run.

But Here’s the Bigger Issue (Especially for Women)

Women’s bodies are more sensitive to stress, especially in the form of:

• Intense training without fuel

• Under-eating

• Poor recovery

Fasted cardio can increase cortisol (your stress hormone), which in the short term isn’t bad—but chronically elevated cortisol?That can lead to:

• Muscle breakdown

• Sleep disruption

• Blood sugar issues

• Fat retention (especially around the belly)

This is even more relevant during perimenopause or menopause, when hormonal balance is already shifting.

Does This Mean Fasted Cardio Is “Bad”?

Not necessarily. Some women feel great doing light cardio before breakfast—like a walk or an easy run. If energy, performance, and recovery are on point, it can be part of your routine.

But if you:

• Wake up feeling depleted

• Struggle with mid-morning crashes

• Have trouble building muscle or losing fat

• Are already under a lot of stress…then fasted cardio may be doing more harm than good.

What I Recommend Instead

If your goal is performance, fat loss, or hormone balance, here’s what works best:

• Eat something small before training. A banana, rice cake with honey, or a Van’s waffle with peanut butter gives your body quick fuel without weighing you down.

• Prioritize post-workout recovery. Get 20–30g of protein and some carbs after training.

• Focus on consistency, not timing. The big picture matters more than whether you had breakfast before your treadmill session.

So, Should Women Do Fasted Cardio?

Maybe. But for most women? It’s not necessary—and often not ideal. Fueling your body = better workouts, better recovery, and a better shot at reaching your goals long-term.

Want a Custom Plan That Actually Works?

If you’re trying to burn fat, feel stronger, and stop guessing about what works for your body—I’m here for you.

Book a free strategy call and let’s build a training and nutrition plan that aligns with your hormones, lifestyle, and goals.

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