Female-Specific Exercise & Nutrition for Health, Performance & Longevity - Dr. Stacy Sims

Why Women Are Not Small Men: The Case for Female-Specific Training

For decades, exercise science treated women as scaled-down versions of men. Study after study was conducted on male subjects, the findings were published, and then those findings were simply applied to women with a note to "adjust for body size." Dr. Stacy Sims has spent her career dismantling this approach with data and clinical evidence, and her conversation with Andrew Huberman lays out exactly why women need different training, nutrition, and recovery strategies from men, especially as they move through perimenopause and into menopause. The differences are not minor. They are fundamental to how women should approach fitness and nutrition during the second half of life.

The hormonal environment in a woman's body creates fundamentally different physiological responses to exercise, food, and stress compared to men. Estrogen and progesterone fluctuate on a monthly cycle during reproductive years, and then decline unevenly and unpredictably during the menopausal transition. These hormones affect everything from how your muscles recover after a workout to how your body selects fuel sources to how your nervous system responds to training stress and perceives pain. Ignoring these differences does more than lead to suboptimal results. It can lead to injury, overtraining, hormonal disruption, and a frustrating sense that your body has stopped responding to things that used to work perfectly well.

Training Through the Menstrual Cycle and Beyond

During the follicular phase, the first half of the menstrual cycle starting from day one of your period, estrogen is rising and women tend to be more resilient to high-intensity work. This is when heavy lifting, sprint intervals, and high-effort training sessions are best tolerated and most productive. Your body is primed for performance during this phase. Recovery is faster, pain tolerance is actually higher, and you have access to carbohydrates as fuel more readily. If you have ever noticed that some weeks your workouts feel amazing and other weeks they feel impossible, this hormonal cycling is likely a major factor.

The luteal phase, the second half of the cycle after ovulation, brings rising progesterone and a different metabolic space. Your body temperature is slightly elevated, which means you overheat more easily during exercise. Your body preferentially burns fat over carbohydrates during this phase, which sounds great on paper but means that high-intensity glycolytic efforts feel harder because those efforts rely on carbohydrate availability. Dr. Sims recommends dialing back the intensity during this phase and focusing on steady-state cardio, moderate resistance training, and skill work. This is not about doing less or being lazy. It is about matching your training to your physiology instead of fighting against it, which produces better results over time than forcing the same approach every day of every month.

Once women enter perimenopause and the cycle becomes irregular or disappears entirely, the playbook shifts again in ways that are counterintuitive for many women. Declining estrogen means your body loses a powerful anabolic and protective signal. Muscle protein synthesis becomes harder to stimulate, which is why Dr. Sims is emphatic that perimenopausal and postmenopausal women need to lift heavy. Not moderate weights for high reps, which is what most women default to. Heavy loads that genuinely challenge your neuromuscular system, weights that you can manage for six to eight reps but not twelve. This is the stimulus your body needs to maintain muscle mass and bone density when estrogen is no longer providing that support through its own pathways.

The Protein and Nutrition Piece

Nutrition for women in midlife is not about eating less. Dr. Sims is adamant on this point, and the research backs her up unequivocally. Caloric restriction in perimenopausal women often backfires spectacularly, increasing cortisol production, accelerating muscle loss, worsening insulin resistance, and paradoxically promoting the very body composition changes women are trying to prevent. The chronic dieting mindset that so many women have carried since their teens and twenties becomes actively destructive during this hormonal transition. Your body reads caloric restriction as a threat, and it responds by conserving energy and storing fat more aggressively.

Instead of eating less, the focus should shift to eating differently and eating enough. Protein is the centerpiece of midlife nutrition. The target Dr. Sims recommends is roughly 1.8 to 2.2 grams of protein per kilogram of body weight per day, distributed across meals with at least 35 to 40 grams per meal for women over 40. This threshold matters because the anabolic resistance that develops with age and declining estrogen means your body needs a stronger protein signal, a higher leucine threshold specifically, to initiate the same muscle-building response that used to happen more easily when you were younger and hormonally replete.

Carbohydrate intake should not be slashed either. Women need carbohydrates to support thyroid function, to fuel high-intensity training performance, and to produce serotonin, the neurotransmitter that supports mood and sleep. Chronically low-carb diets can suppress T3 (the active thyroid hormone), worsen sleep quality, tank mood, and increase cortisol in women. The "just cut carbs" approach that works for some men in the short term can be actively harmful for many women, especially during the menopausal transition when every hormonal system is already under stress. The timing and type of carbohydrates can be adjusted around training, but the total amount should be adequate to support your activity level and your hormonal needs.

High-Intensity Interval Training: The Non-Negotiable

One of the strongest and most specific recommendations Dr. Sims makes is for true high-intensity interval training, and she is clear about what she means because the fitness industry has diluted this term beyond recognition. She does not mean the watered-down version most gym classes call HIIT, which is really just circuit training at moderate intensity. She means genuine all-out efforts of 30 seconds or less, followed by full recovery periods of two to four minutes. Sprint intervals on a bike, rowing sprints, or short hill runs where you give maximum effort and then rest completely before the next interval.

These brief maximal efforts stimulate growth hormone release, improve insulin sensitivity dramatically, and provide the intense neuromuscular stimulus that perimenopausal women specifically need to counteract the effects of declining hormones. The growth hormone response from true HIIT is one of the most powerful natural tools available for combating the body composition changes of menopause. This kind of training also has outsized effects on cardiovascular health, which becomes increasingly important as estrogen's cardioprotective effects diminish. Your heart needs to work at high intensities periodically to maintain its functional capacity and its structural integrity. Steady-state cardio alone cannot provide this stimulus.

Recovery and Sleep: Where It All Comes Together

Sleep disruption is one of the hallmark symptoms of perimenopause, and it creates a vicious cycle that amplifies every other problem. Poor sleep elevates cortisol, increases insulin resistance, reduces growth hormone secretion that normally occurs during deep sleep, and makes everything from training recovery to mood regulation to food choices harder. Many women in perimenopause feel like they are falling apart, and inadequate sleep is often the accelerant that turns manageable symptoms into an overwhelming cascade.

Dr. Sims acknowledges this challenge directly rather than dismissing it with generic sleep hygiene advice. Her practical strategies include tart cherry juice as a natural melatonin source, keeping the bedroom aggressively cool (the temperature regulation issues of perimenopause make this even more important than it is for the general population), and using magnesium glycinate or threonate before bed for its calming and sleep-promoting effects. These are not cure-alls, but they are targeted interventions that address the specific physiology of perimenopausal sleep disruption.

Recovery between training sessions also needs to be addressed differently for midlife women compared to younger athletes. The inflammatory response to exercise may be heightened when estrogen is low because estrogen is itself a powerful anti-inflammatory agent. This means recovery takes longer, soreness may be more pronounced, and the risk of overtraining is higher if you do not adjust your expectations and your training schedule. Building in adequate rest days, prioritizing sleep as a training tool rather than an afterthought, and using anti-inflammatory nutrition strategies like omega-3 fatty acids, colorful vegetables, tart cherry, and turmeric can help manage the recovery burden.

Building Your Midlife Training Plan

Putting this all together, Dr. Sims outlines a practical and sustainable framework for women in perimenopause and beyond that looks quite different from what most women are currently doing. Two to three days per week of heavy resistance training, focusing on compound movements like squats, deadlifts, bench presses, overhead presses, and rows. One to two days of true HIIT with full recovery intervals between efforts. One to two days of lower-intensity movement like walking, yoga, swimming, or easy cycling. And critically, rest days that are actually restful, not crammed with another workout because you feel guilty for not exercising.

This is not about doing more volume or grinding harder through fatigue. It is about doing the right things at the right intensity at the right time. The women who thrive during the menopausal transition are not the ones who train the hardest or eat the least. They are the ones who stop training like they did at 25 and start training in a way that respects and works with their current physiology rather than against it. Dr. Sims has given women a science-backed roadmap for exactly that, and this conversation with Huberman makes it accessible and actionable for anyone willing to listen and implement.

Your body is not failing you during this transition. It is changing in ways that are predictable, understandable, and manageable with the right approach. The tools to change with it, effectively and with confidence, are grounded in solid exercise science and clinical evidence. You just need to use them consistently and stop applying strategies that were designed for a different hormonal reality than the one you are living in now.