Podcast Summary: Habits and Hustle Episode 466: Dr. Stacy Sims: Why Women Can't Fast Like Men + The Training Intensity You Should Avoid Release Date: July 11, 2025
Host: Jennifer Cohen
Guest: Dr. Stacy Sims

Introduction

In Episode 466 of Habits and Hustle, host Jennifer Cohen engages in an enlightening discussion with renowned exercise physiologist and nutrition scientist, Dr. Stacy Sims. The episode delves deep into the unique physiological responses of women to training, fasting, and nutritional needs, particularly during perimenopause and menopause. Dr. Sims provides evidence-based insights that challenge common fitness and nutrition paradigms, offering tailored advice for women striving to achieve optimal health and performance.

The Importance of Recovery in Women's Training

Polarized Training Approach
Dr. Sims emphasizes that women often underestimate the necessity of recovery in their training regimes. She advocates for a polarized training model, which avoids the "middle zone" of intensity to optimize performance and recovery.

“Polarized means that you're staying out of that middle zone so you can go super hard when you need to and you recover super easy.”
— Dr. Stacy Sims ([01:53])

In this model, women engage in high-intensity sessions interspersed with easy recovery periods, enhancing both performance and sustainable training habits.

Recommended Training Frequency
Dr. Sims outlines a balanced weekly training schedule, suggesting a minimum of two sprint interval sessions or one sprint and one high-intensity session, complemented by three lifting sessions.

“It's about the quality of the work that you're doing rather than the volume of the work that you're doing.”
— Dr. Stacy Sims ([02:58])

Jump Training and Bone Health

Benefits of Jump Training
Dr. Sims explains that jump training is crucial for bone density and overall skeletal health due to its multidirectional stress, which stimulates bone regeneration.

“Jumping does that because you're landing and it's complete stress in all the different planes that go up through the skeletal system...”
— Dr. Stacy Sims ([03:03])

Effective Jump Training Techniques
She distinguishes effective jump training from activities like trampoline jumping, highlighting the importance of ground impact for bone strength.

“Absorbing the impact through our bones.”
— Dr. Stacy Sims ([03:52])

Practical Application
Dr. Sims recommends incorporating jump training for just 10 minutes, three times a week, to see significant benefits in bone density.

Women and Fasting: A Hormonal Perspective

Challenges of Fasting for Women
Dr. Sims critiques popular fasting trends, particularly for women in perimenopause and menopause, pointing out that prolonged fasting can disrupt hormonal balance and muscle maintenance.

“Women are more sensitive to no calories because we are the ones that are or were responsible for reproduction...”
— Dr. Stacy Sims ([07:47])

Biological Differences in Fasting Responses
She elaborates on the sex-specific differences in the hypothalamus, which makes women more susceptible to hormonal disturbances from fasting compared to men.

Optimal Fasting Practices for Women
Dr. Sims recommends a moderate approach to fasting, such as a 12-hour eating window, to balance hormonal health and metabolic needs.

“We need to eat within a half an hour of waking up because we have a cortisol peak...”
— Dr. Stacy Sims ([04:57])

Nutritional Needs: Protein Intake for Women

Plant-Based Protein Strategies
Dr. Sims shares her personal experience with a plant-based diet and provides strategies for meeting protein needs without animal products.

“It's really understanding nutrition and I think that's one of the, the lacking points is the education around it.”
— Dr. Stacy Sims ([14:46])

Recommended Protein Intake
She stresses that women, especially those over 40, require higher protein intake to combat anabolic resistance and maintain lean mass.

“Women really need to dial it up because that recommendation that is based on the bare minimum to prevent malnutrition is still circulating as the needs for people.”
— Dr. Stacy Sims ([09:43])

Top Plant-Based Protein Sources
Dr. Sims identifies tempeh, spirulina, and pea protein isolate as excellent sources for those avoiding animal proteins.

Essential Supplements for Women's Health

Top Three Supplements
Dr. Sims outlines three fundamental supplements crucial for women's health:

1. Creatine Monohydrate
   Essential for brain, gut, and heart health, particularly effective for vegetarians and vegans.

   “Creatine monohydrate for sure.”
   — Dr. Stacy Sims ([16:38])

2. Omega-3 Fatty Acids
   Supports antioxidant capacity and cellular health, vital for perimenopausal women.

   “Omega 3 fatty acids.”
   — Dr. Stacy Sims ([16:38])

3. Vitamin D3
   Important for bone health, iron absorption, and overall bodily functions, especially in regions with limited sunlight.

   “Vitamin D3.”
   — Dr. Stacy Sims ([16:38])

Supplements to Avoid or Use Cautiously
She advises against certain supplements like beet juice for premenopausal women due to adverse interactions with estrogen and vessel function.

“Beet juice... has a backwards effect... orthostatic hypotension.”
— Dr. Stacy Sims ([16:51])

Addressing Common Health Issues: Fiber Deficiency

Impact of Low Fiber Intake
Jennifer Cohen highlights the widespread issue of fiber deficiency, which affects 95% of the population, underscoring its critical role in digestion, gut microbiome health, satiety, energy levels, and blood sugar stability.

“Fiber is truly the foundation of overall wellness.”
— Jennifer Cohen ([11:13])

Solutions for Fiber Intake
She introduces Biome’s daily prebiotic fiber supplement as an effective way to bridge the fiber gap, making it easier for individuals to meet their daily requirements.

Conclusion

The episode provides a comprehensive exploration of how women can tailor their training, fasting, and nutritional strategies to align with their unique physiological needs. Dr. Stacy Sims empowers women with knowledge to make informed decisions that enhance their health, performance, and overall well-being during critical life stages such as perimenopause and menopause.

For listeners seeking to optimize their fitness routines and nutritional intake, Episode 466 offers invaluable insights backed by scientific research and practical recommendations.

Notable Quotes:

• “Polarized means that you're staying out of that middle zone so you can go super hard when you need to and you recover super easy.” — Dr. Stacy Sims ([01:53])

• “Women are more sensitive to no calories because we are the ones that are or were responsible for reproduction...” — Dr. Stacy Sims ([07:47])

• “Fiber is truly the foundation of overall wellness.” — Jennifer Cohen ([11:13])

This summary encapsulates the key discussions and insights shared by Dr. Stacy Sims and Jennifer Cohen, providing a clear roadmap for women aiming to enhance their health and fitness through informed habits and sustainable practices.