Stop Training Fasted? Protein Timing That Boosts Fat Loss in Women — Dr. Katie Hirsch

Fasted training is one of the most persistent fat-loss myths—and in this episode, Dr. Katie Hirsch breaks down what actually matters for women: training quality, muscle preservation, and metabolic health.

We unpack why "burning more fat during a workout" is often the wrong target, and how a small amount of protein (or EAAs) before training can change perceived exertion, improve workout output, and potentially increase post-workout energy expenditure—especially in women who are prone to under-fueling.

We also dive into muscle quality (not just muscle size), why it matters for insulin sensitivity and body composition, and what changes in peri/post-menopause can mean for amino acid delivery to muscle—and how to train and eat to stay lean, strong, and metabolically resilient.

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Episode Topics Covered

• Fasted vs. fed training for fat loss

• Protein vs. carbs pre-workout

• Energy availability and women's physiology

• Essential amino acids + HIIT

• Muscle turnover, energy expenditure, and fat oxidation

• Protein timing, dosing, and distribution

• Muscle quality (echo intensity), intramuscular fat, and metabolic health

• Adiposity spillover, visceral fat, and muscle infiltration

• Perimenopause/postmenopause, estrogen, vascular function, and anabolic resistance

• Simple strategies for sustainable body recomposition

Dr. Katie Hirsch is an exercise physiologist and sports nutrition researcher focused on protein metabolism, body composition, energy expenditure, HIIT, muscle quality, and female-specific physiology, including changes across perimenopause and postmenopause.

(As mentioned in the episode: she's wrapping up publications on improved methods to characterize hormone profiles and exploring new ways to use bioelectrical impedance outcomes like phase angle to better capture muscle quality and related physiology.)

Protein-Sparing Modified Fasting Library (Coming Soon)

Vanessa shares her behind-the-scenes system built from the approach she used to lose 14+ lbs of body fat while preserving lean mass.

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The content provided in this podcast is for informational purposes only and should not be construed as medical advice. Consult with a healthcare professional before making significant changes to your diet or exercise regimen.