The Exercise & Nutrition Scientist: The Truth About Exercising On Your Period! Women Were Right About Menopause! These 4 Supplements Give Women Optimal Health!
Dr. Stacey Sims, an exercise physiologist and nutrition scientist, discusses how women's unique physiology, influenced by hormonal changes across life stages, requires tailored approaches to exercise, nutrition, and recovery, challenging male-centric sports science.
Deep Dive Analysis
21 Topic Outline
The Problem with Male-Centric Sports Science Research
Dr. Sims' Academic Journey and Research Focus
Fundamental Physiological Differences Between Sexes
Q-Angle and ACL Injury Risk in Women
Addressing Quad Dominance and ACL Injury Prevention
Historical Bias: Women as Smaller Versions of Men in Science
Sex-Specific Weight Loss and Fasting Advice
The Hypothalamus and Nutrient Sensitivity in Women
Exercise as a Stronger Stimulus for Autophagy than Fasting
Ozempic and the Importance of Behavioral Change
Post-Exercise Nutrition Timing for Men vs. Women
Keto Diet's Impact on Gut Microbiome and Women's Hormones
Sex Differences in Sauna and Cold Plunge Benefits
Creatine Supplementation for Women: Dispelling Myths
Essential Supplements for Women: Vitamin D and Iron
Adapting Nutrition and Exercise to the Menstrual Cycle
Sleep, Jet Lag, and Chronotypes: Sex Differences
Understanding Perimenopause and Menopause
Exercise and Nutrition Strategies for Menopause
Menopause Hormone Therapy vs. Hormone Replacement
Nutrition and Exercise for Endometriosis and PCOS
6 Key Concepts
Q-Angle
The Q-angle refers to the angle formed by the knee to the hip. Due to wider hips, women have a larger Q-angle compared to men, which can change running mechanics and predispose them to certain injuries like ACL tears because forces aren't distributed evenly through the knee.
Quad Dominance
Quad dominance in women means they tend to use the front muscles of their legs (quads) significantly more than their hamstrings and glutes (posterior chain). This imbalance, combined with the Q-angle, increases the risk of ACL injuries as it pulls forces forward and misaligns stress on the knee.
Hypothalamus Sensitivity
The hypothalamus, the brain's control center for appetite and endocrine function, is more sensitive to nutrient density in women than in men. This means women's bodies perceive low calorie or carbohydrate intake as a significant stressor, potentially leading to muscle loss and hormonal dysfunction, unlike men whose bodies may adapt by tapping into stored fuel.
Low Energy Availability
This occurs when an individual, particularly women, does not consume enough calories to support their daily energy expenditure, including exercise and basic bodily functions. It can lead to the hypothalamus winding down essential systems like the reproductive cycle, resulting in missed periods, poor bone health, and other endocrine dysfunctions.
Circadian Misalignment
This refers to a disruption in the body's natural 24-hour internal clock, often caused by late eating, screen time, or shift work. For women, this misalignment can specifically increase cravings for carbohydrates, lead to a feeling of never being full, and negatively impact sleep architecture and blood glucose control.
Menopause Hormone Therapy
This is a therapeutic approach for women experiencing perimenopause and menopause, using a very low physiological level of hormones to attenuate severe symptoms and changes. It is distinct from 'hormone replacement' because the goal is not to restore hormone levels to reproductive years but to manage symptoms and improve quality of life during this phase.
11 Questions Answered
Historically, recruitment for studies has been geared towards men, often using aggressive language in sport that is off-putting to women. Limited funding also leads researchers to recruit subjects who can commit consistently, which has often been 18-22 year old college-age men, and most study designers have been men.
During puberty, girls' hips and shoulders widen, causing their center of gravity to drop and changing the angle of the knee to the hip (Q-angle). Boys, in contrast, get leaner, faster, and more aggressive, with their bodies becoming more linear.
Women's hypothalamus is more sensitive to nutrient density, perceiving low calorie or carb intake as a famine, which can lead to the body conserving energy, winding down the reproductive system, and burning lean muscle mass. Men's hypothalamus is less sensitive, allowing them to tap into stored glycogen and lean up.
Yes, women should aim to eat within 45 minutes post-exercise to maximize muscle protein synthesis and recovery, as their metabolism returns to baseline much faster (30-40 minutes) than men's (2-18 hours). For women in reproductive years, 35 grams of protein is recommended post-exercise.
Dr. Sims is generally anti-keto for both sexes due to its negative impact on gut microbiome diversity, which is crucial for women's sex hormone metabolism. The high fat intake on a ketogenic diet can lead to an overgrowth of certain bacteria, reducing the beneficial bacteria that thrive on diverse fibrous plants.
For women to experience the same physiological benefits that men get from ice water (0-4 degrees C), the optimal cold plunge temperature is around 15-16 degrees Celsius (55 degrees Fahrenheit). Colder temperatures can be too much of a threat due to differences in skin sensation and thermoregulation.
For general health benefits, women are recommended to take 3 to 5 grams of creatine once a day, without carbohydrate. This dosage helps saturate the body over about three weeks, improving gut health, brain metabolism, and muscle capacity without the water weight gain associated with higher bodybuilding doses.
Bone health in women is critically driven by estrogen and progesterone, with peak bone mass typically reached around age 20. Fluctuations in these hormones throughout the menstrual cycle and their decline during menopause significantly impact bone density, making women more susceptible to degradation, osteopenia, and osteoporosis.
Women experience changes in sleep phases across their menstrual cycle, with more interruptions in deep sleep closer to the bleed phase due to hormonal interference (progesterone increasing core temperature, estrogen affecting melatonin). Men do not have these hormonal perturbations and tend to have a later melatonin peak, allowing them to stay up later and potentially have shorter sleeps.
Perimenopause is the transitional phase leading up to menopause, typically starting around age 35 and lasting until the average age of menopause (52 years old). During this period, women experience significant changes in the ratio of estrogen and progesterone, leading to symptoms like disrupted sleep, mood changes, increased body fat, and difficulty adapting to training.
During perimenopause and menopause, women should focus on high-intensity interval training (HIT), plyometrics (jumping), and power-based resistance training (3 times a week) to create external stress that promotes insulin sensitivity, glucose storage, and fat utilization. The focus should be on less volume and more quality in training.
27 Actionable Insights
1. Avoid Fasted Training for Women
Women should consume a small amount of protein (e.g., 15g) or protein with carbohydrates (e.g., 15g protein + 30g carb) before cardio and strength training to prevent burning lean muscle mass and support metabolic function, as their hypothalamus is more sensitive to low blood sugar.
2. Rapid Post-Workout Protein for Women
Women in their reproductive years should consume 35 grams of protein within 45 minutes after exercise to maximize muscle protein synthesis, as their metabolic recovery window is much shorter than men’s.
3. Embrace Resistance Training for Women
Women aiming for body composition changes should prioritize resistance training and increase protein intake, as it is crucial for mobilizing abdominal fat, building lean mass, and improving metabolic signaling.
4. Daily Creatine for Women’s Health
Women should take 3-5 grams of creatine monohydrate daily (without carbohydrate) to improve gut mucosal lining integrity, reduce GI distress, enhance brain metabolism, and potentially alleviate symptoms of depression and anxiety. A loading phase is not necessary for these benefits.
5. Optimize Fasting with Circadian Rhythm
For women, practice an overnight fast by stopping eating 2-3 hours before bed and consuming food within 30 minutes of waking to blunt the natural cortisol peak and support metabolic health. Avoid extended fasting protocols like warrior fasts, which can negatively impact women’s blood sugar control and thyroid function.
6. Monitor Bleed Pattern for Stress Cues
Track your bleed pattern and menstrual cycle length, as changes can indicate that your body is not adapting well to stress (e.g., over-training, under-eating, daily life stress), signaling a need to pause and reassess your lifestyle.
7. Personalize Training with Perceived Exertion
Women should track their menstrual cycle by monitoring how they feel daily (physical and mental perceived exertion) to identify patterns and adapt training intensity, allowing for high-intensity work during stronger phases (e.g., follicular) and recovery/technique days during weaker phases (e.g., late luteal).
8. Adjust Carb/Protein Post-Ovulation
After ovulation (roughly day 14 onwards), women should increase carbohydrate intake before and after high-intensity workouts and increase protein intake by about 12% to support energy needs and tissue development, as higher progesterone levels can cause insulin resistance and increased amino acid demand.
9. Increase Protein and Gut Diversity in Perimenopause
Increase protein intake to combat anabolic resistance and support muscle, bone, and nerve regeneration during perimenopause. Maintain gut microbiome diversity with a wide variety of colorful fruits and vegetables to aid blood glucose control and reduce fat storage.
10. Quality Over Volume in Perimenopause
During perimenopause, prioritize short, sharp, high-intensity cardio (2-4 times/week) and power-based resistance training (3 times/week) over long, moderate sessions to effectively stimulate adaptive changes, improve insulin sensitivity, and mobilize visceral fat.
11. Strengthen Hamstrings for ACL
Women should focus on strengthening their hamstrings and the entire posterior chain (glutes, hamstrings, calves) to balance forces across the knee, reducing the high incidence of ACL injuries common in women due to their Q-angle and quad dominance. Incorporate explosive lateral movements, jumping, and single-leg jumping.
12. Educate Girls on Body Changes
Teach girls about physiological changes during puberty, such as the Q-angle shift, lower center of gravity, and quad dominance, to help them adapt their movement mechanics for running, swimming, and jumping, preventing sport dropout.
13. Avoid Ketogenic Diet for Gut Health
Avoid ketogenic diets due to their significant negative impact on gut microbiome diversity, which is crucial for overall health and sex hormone metabolism in women. Instead, aim for a diverse intake of 30 different plants per week to foster beneficial gut bacteria.
14. Supplement Vitamin D3
Supplement with Vitamin D3, especially in winter or with limited sun exposure, as it is crucial for recovery, muscle function, brain health, and overall systemic well-being, affecting nearly every system in the body.
15. Monitor and Supplement Iron
Women, particularly active ones, should aim for ferritin levels of 50-100, supplementing with a highly bioavailable iron (e.g., carbonyl or glycanate) every other day, either before training or at night, to avoid fatigue and support oxygen carrying capacity.
16. Integrate Lifestyle with Ozempic
If using medications like Ozempic for weight loss, simultaneously learn and implement proper strength training, exercise modalities, and nutrition to support sustainable weight loss and prevent weight regain upon cessation, as rapid weight loss from such tools often involves lean mass.
17. Prioritize Exercise for Autophagy
Engage in regular exercise as it provides a stronger stimulus for autophagy (cellular cleanup and repair) and adaptive changes than most fasting protocols, offering significant longevity and metabolic benefits.
18. Adjust Cold Plunge Temperature for Women
Women should use cold water immersion at 15-16 degrees Celsius (around 55 degrees Fahrenheit) to achieve the same physiological benefits as men in ice baths, as colder temperatures (0-4 degrees C) can be too much of a threat due to thermoregulation differences and more subcutaneous fat.
19. Align Eating with Circadian Rhythm
Stop eating 2-3 hours before bed to allow the body’s parasympathetic system to focus on sleep and recovery rather than digestion, improving sleep architecture and overall metabolic health. Eating late can shift metabolism and increase carbohydrate cravings for women.
20. Manage Sleep Around Menstrual Cycle
Women should be aware that hormonal shifts, particularly before their menstrual cycle, can disrupt sleep phases due to increased core temperature and altered melatonin pulses, requiring proactive sleep management. Also, anticipate greater jet lag when traveling west due to chronobiology differences.
21. Consider Omega-3s for Inflammation
Women in peri- and post-menopause should consider supplementing with a good Omega-3 fish oil, especially after checking blood levels, to help manage inflammation and enhance cellular integrity as estrogen’s anti-inflammatory properties decline.
22. Extend Sauna Time for Women
Women require longer durations in the sauna, both for acute sessions and over weeks, to achieve the same cardiovascular adaptations as men, due to differences in vasodilation and core temperature response.
23. High-Intensity Training for PCOS
Women with PCOS should focus on high-intensity and resistance training to manage insulin resistance and attenuate symptoms, especially given irregular cycles make cycle-based tracking difficult.
24. Cold Therapy for Endometriosis
For endometriosis, consider using cold water therapy or a cold plunge around ovulation to reduce the inflammatory response and limit the growth of endometrial tissue outside the uterus.
25. Prioritize Bone-Loading Exercise
Engage in multi-directional stress exercises like jumping and resistance training throughout life to maintain and build bone density, which is crucial for women due to hormonal influences on bone health.
26. Easy-to-Digest Protein for Focus
If you need to concentrate or articulate well, consume easy-to-digest, high-protein foods like a protein shake, protein water, or hard-boiled eggs beforehand, rather than fasting, to provide fuel without impacting mental clarity.
27. Eat with Caffeine for Women
Women should eat when consuming caffeine, especially during exercise, because caffeine clears blood sugar quickly and their bodies process fuel differently than men, preventing rapid blood sugar depletion.
5 Key Quotes
If we're looking at sports science research, everything from training to eating, recovery, it's based on male data. And women have been generalized to that data.
Dr. Stacy Sims
The problem is it's never about how we can empower women to use their physiology to their advantage.
Dr. Stacy Sims
If you go in and you're low on both of them, then it's going to be a technique in recovery day. You're not wasting time at the gym.
Dr. Stacy Sims
It gets better on the other side. I think that's something people don't talk about is perimenopause is such the conversation now with all the conversations around hormone therapy, exercise, lifestyle, but no one talks about the other side.
Dr. Stacy Sims
I knew we had made it as women in society when the nightly news was talking about menopause.
Dr. Stacy Sims
5 Protocols
ACL Injury Prevention for Women
Dr. Stacy Sims- Improve strength capacity of hamstrings to offset quad dominance, balancing front-loaded with even-loaded forces.
- Develop strength through the entire posterior chain, including glutes and calves.
- Incorporate explosive lateral movements into training.
- Practice jumping and single-leg jumping techniques.
Fasting for Women (Health Benefits)
Dr. Stacy Sims- Stop eating at dinner, ensuring no food intake 2 to 3 hours before bed.
- Maintain an overnight fast.
- Consume food within half an hour of waking up to blunt the natural cortisol peak.
Adapting Exercise to the Menstrual Cycle
Dr. Stacy Sims- During the low hormone (follicular) phase (Day 1 to ovulation, approx. Day 12-13): Push hard, aim for personal records (PRs), and focus on high-intensity work.
- After ovulation (approx. Day 14 onwards): Shift to more endurance and tempo-type work, potentially reducing high intensity.
- Approximately 4 to 5 days before your period starts: Use this time as a deload phase, focusing on recovery, mobility, and avoiding high-intensity workouts due to a compromised immune system.
Exercise Strategy for Perimenopause and Menopause
Dr. Stacy Sims- Incorporate high-intensity interval training (HIT) or true high-intensity work to improve insulin sensitivity and glucose control.
- Perform power-based resistance training three times a week.
- Include cardio training two to four times a week.
- Focus on less training volume and more quality in each session.
Iron Supplementation for Women
Dr. Stacy Sims- Supplement every other day with a high bioavailable iron (e.g., carbonyl or glycinate).
- Time supplementation before training or at night, away from training, to avoid interference from hepcidin (an enzyme that decreases iron absorption and increases with inflammation post-exercise).