Why Women Shouldn’t Work Out Fasted - And How This Could Be Ruining Your Progress

Fasted workouts have become trendy for those hoping to burn fat and “hack” metabolism. But for women, training on an empty stomach might actually backfire.

There have been many studies which have highlighted important sex differences in how the body responds to fasting and exercise. These studies, which include discussions on metabolism and hormones, explain that while fasted training can benefit some men, it can increase stress hormones like cortisol in women, potentially disrupting menstrual cycles, sleep, and recovery. Elevated cortisol can also make it harder to build muscle or lose stubborn body fat - the exact opposite of many women’s fitness goals.

Women’s bodies are more sensitive to energy availability due to reproductive hormone balance. Exercising without fuel can signal the body that it’s under stress or in a starved state, leading to hormonal adaptations that slow metabolism and compromise progress. So while their male counterparts are burning fat easily in a fasted state, women are not and may even gain body fat.

Instead of fasted workouts, women will see more positive results by having a small pre-workout meal or snack - even something simple like a piece of fruit or coffee with milk if it’s early in the morning - to keep stress hormones in check and support performance.

If you’re a woman aiming for sustainable fat loss, muscle gain, or simply good health, it’s worth reconsidering whether fasted training is helping or hindering your results.

Fuel Smarter, Train Stronger

Understanding your body’s response to exercise is empowering—and wearing gear that supports strength, comfort, and function makes it practical. At KoaKoa Active, we design performance-driven activewear for real women in motion.

Equip yourself with purposeful gear:

• Shop the newest styles in New Arrivals designed for moves that matter.
• Find your go-to Active Bottoms leggings and shorts that stay in place from warm-up to cooldown.
• Secure your sessions with a reliable Sports Bra, crafted for both comfort and support.
• Go from workout to recovery in breathable Tops that flex for any flow.

References:

Huberman Lab Podcast, Episodes on Metabolism & Hormones (e.g. “Using Science to Optimize Fat Loss,” 2023)

Written by healthywith_zoe