The Impact of Fasted Workouts on Women

I get asked this question a lot and this is an area I have been adjusting in my own routine. I never work out fast on purpose, but since I wake up so early to workout I got into a bad routine of just drinking coffee and jumping into my workout. I knew this wasn’t ideal, but I got lazy. I have recently been diving into the research more on intermittent fasting and fasted workouts and how it impacts women’s health and hormones.

A fasted workout is when a workout takes place after not eating for 10–12 hours, or being in an fasted state, and means that the body’s glycogen (aka carb) stores are depleted and it has stopped breaking down food. In theory, this can lead to forcing the body to use fat for fuel in the absence of glycogen. This may be true in men, but sadly fasted training affects women differently.

Here are some important highlights I’ve learned from my research:

• Cortisol is highest in the morning and by adding in the stress of an intense workout in a fasted state this can cause cortisol to remain chronically high and reduces your ability to relax.

• Women have a greater sensitivity to changes in their energy balance. This energy balance is disrupted through fasted cardio, as your brain perceives a deficiency in nutrients.

• If women train fasted, they’re more likely to tap into lean muscle (NOT FAT!) as an energy source because the body is trying to conserve all fat and carbohydrate stores for critical reproductive functions.

• Working out fasted you may experience symptoms of low blood sugar caused by going so long without eating. If you don’t feel your best or energetic during a fasted workout, it’s also likely your performance will suffer and you won’t get the full benefits of the workout

• Sipping a meal to exercise in a fasted state can also lead to chronic under eating which can lead to muscle and bone loss, disrupt hormones and cause burnout.

• Training in a fed state could be better for female hormones and overall athletic performance

Bottom line, the long-term effects for females working out in a fasted state can result in hormonal dysfunction which can lead to increased abdominal fat and potential fat gain and may even cause anxiety and depression. It’s so important for females to workout in a fed state for physical AND mental health.

Training in a fed state can increase athletic performance, improve blood sugar balance throughout the day, improve appetite regulating hormones and reproductive hormones.

I listened to a podcast with Dr. Stacy Sims and she recommends  consuming 15g of protein before resistance training and 15g of protein + 30g of carbs before cardio. If you’re exercising over 90 minutes then you need to refuel during your workout.

The timing of eating can vary depending on when you’re exercising and how sensitive you are to certain foods before exercise. Some people can eat 30 minutes before activity and others need to eat more like 1-2 hours before training. It’s important to experiment with different foods and timing to see what works best for you.

All of this to say, women simply do better training in a fueled state. Since I tend to workout first thing in the morning I have started to have a protein coffee before my workout. I have 2 shots of espresso with 1 cup sweetened (carbs) oat milk and 1 scoop protein powders (15-20 grams protein).

xx, A