The Performance Variable No One Talks About (But Should): Female Cycle, Perimenopause, and HRT For Women

I won't give any names, but my 11-year-old daughter has just entered puberty.

The house has become a hormonal battlefield. One moment, she's belting out Taylor Swift lyrics with pure joy. Next, she's declaring war over the breakfast cereal choice. The emotional swings are spectacular—and completely normal.

Watching this transformation reminded me of something I'd somehow forgotten despite years of medical training: I know almost nothing about how female hormones actually work in the real world.

Sure, I studied reproductive physiology. Aced the obstetrics rotation. Memorized estrogen and progesterone cycles like any good medical student. But understanding the textbook version of hormonal fluctuations and witnessing the raw power of those changes in your own home? Completely different games.

That realization sent me down a research rabbit hole that changed my perception of performance, optimization, and longevity. Because here's what nobody wants to admit: we've been ignoring the most significant performance variable affecting half the population.

The stakes couldn't be higher. Women hit their career peaks exactly when their hormones stage a biological revolution. They're told to suffer in silence during transitions that could be optimized. They're fed myths about their own bodies that undermine their potential.

This is the heart of our Upward ARC framework's Activate pillar—you can't optimize what you refuse to understand.

The Performance Myth That Fooled Everyone

For decades, everyone believed the same story about female performance. Hormonal fluctuations wreck consistency. Menstrual cycles sabotage athletic output. Women are biological victims of their own physiology.

The story was so convincing that researchers built entire studies around it. Coaches planned training cycles to accommodate it. Female athletes internalized it as a biological fact.

Then science pulled the rug out from under everyone.

A 2020 systematic review analyzed 78 studies and 1,193 women to finally quantify the hormonal performance disaster. Researchers expected to map the chaos to prove what everyone already "knew" about female unreliability.

The results were devastating. To the myth, not the women.

Performance impact across menstrual cycle phases? Less than 2%. Statistically trivial. Practically meaningless.

The research revealed something far more interesting than hormonal chaos: individual patterns matter infinitely more than universal cycles. Some women feel strongest during their period, while others peak mid-cycle. Many notice zero correlation between hormones and performance.

Serena Williams won the Australian Open while pregnant. Katie Ledecky set world records at every phase of her cycle. The data doesn't lie: hormones don't predetermine performance limits.

But we keep acting like they do.

The Instagram Science Problem

Enter the "cycle syncing" revolution. Social media exploded with protocols promising to unlock your hormonal superpowers: Train hard during the follicular phase. Rest during the luteal phase. Eat specific foods on specific days.

The marketing was brilliant. The science? Embarrassingly thin.

The American College of Sports Medicine put it bluntly: no substantial evidence supports manipulating training or diet around cycle phases for performance optimization. The research simply isn't there.

Yet the trend persists because it sells a seductive promise: work with your body, not against it. Follow the protocol, and optimize your life.

Here's the actual truth: your body didn't read the same Instagram posts you did.

Individual tracking beats generic protocols every time. Notice when you feel strongest. Pay attention to recovery patterns. Adjust based on your data, not someone else's template.

For executives, this means scheduling flexibility around personal patterns, not rigid adherence to apps that don't know your biology.

The Midlife Ambush

The real hormonal drama begins when most women hit their professional stride. Perimenopause typically starts in the 40s: peak career years, maximum responsibility, and decades of investment paying off.

That's when biology stages its coup.

The hormonal chaos of perimenopause makes teenage hormone swings look quaint. Estrogen levels don't just decline—they fluctuate wildly before crashing. The effects ripple through every system.

The Study of Women's Health Across the Nation tracked thousands of women through this transition. The findings should terrify every ambitious professional: fat gain doubles during the menopausal transition. Muscle loss accelerates. Bone density plummets.

The metabolic consequences are brutal. Estrogen regulates insulin sensitivity and fat distribution. Without it, the body shifts toward storing dangerous visceral fat. The "menopause belly" isn't cosmetic—it's a cardiovascular time bomb.

Cognitive effects can be equally devastating. "Brain fog" during perimenopause isn't imagination—it's measurable changes in memory, concentration, and mental clarity. Perfect timing for your most demanding professional years.

Night sweats destroy sleep. Hot flashes disrupt meetings. Energy crashes at the worst possible moments.

Most women suffer through this transition, believing it's inevitable. It's not. Biology can be managed, optimized, or even leveraged. But only if you understand what's happening and fight back strategically.

The Treatment That Became a Villain

Hormone replacement therapy was crucified after 2002. The Women's Health Initiative study linked HRT to breast cancer and heart disease. Doctors stopped prescribing it. Women stopped asking for it. Suffering became a virtue.

Twenty years later, the whole story emerged. The study examined older women using specific hormone formulations barely used today. Context mattered. Age mattered. Timing mattered.

The current medical consensus from leading organizations is that for healthy women under 60 starting HRT within 10 years of menopause, the benefits generally outweigh the risks.

HRT remains the gold standard for menopausal symptoms. Nothing else comes close to preventing hot flashes, night sweats, and sleep disruption. It also prevents bone loss and may preserve muscle mass and cognitive function.

The transformation can be dramatic for high performers. Better sleep equals sharper thinking. Fewer hot flashes mean confident presentations. Stable energy drives sustained performance.

Modern HRT uses bioidentical hormones delivered through patches or gels. Dosing is personalized. Risks are carefully managed. This isn't your mother's hormone therapy—it's precision medicine.

The decision framework is simple: Are symptoms affecting your performance? Do you have contraindications? Will you accept small, manageable risks for significant quality-of-life gains?

If yes, HRT deserves serious consideration. If not, focus on lifestyle interventions that also work; just not as powerfully.

The Billion Dollar Revolution

FemTech represents a rapidly growing sector with hundreds of startups and billions in investment. This isn't just period tracking anymore.

Wearables predict cycle phases through temperature, heart rate, and sleep patterns. The Oura Ring detects ovulation with remarkable accuracy. WHOOP correlates recovery with hormonal fluctuations. AI algorithms provide personalized optimization recommendations.

This technology offers unprecedented advantages for professionals. Imagine knowing when your focus peaks, when stress resilience is highest, and when recovery capacity is optimal. That's not future science—it's available today.

Continuous hormone monitoring is coming. Real-time data on estrogen, progesterone, and cortisol will revolutionize how we optimize female physiology. The technology exists; the only barrier is regulatory approval.

The Professional’s Playbook

Four strategies for immediate implementation:

The Pattern Recognition Protocol

Track cycle phases alongside performance metrics for three months. Note energy, sleep quality, cognitive clarity, and workout performance. Look for personal patterns, not universal truths. Use any period app or a simple spreadsheet. If you consistently feel sharper during certain cycle days, schedule crucial meetings then.

The Midlife Defense Strategy

Resistance training becomes non-negotiable after 40. During hormonal transitions, heavy compound movements—squats, deadlifts, presses—preserve muscle and bone density. Two to three sessions weekly. Progressive overload. Hire a trainer if needed. Consider it insurance against future decline.

The HRT Decision Matrix

Find healthcare providers who are current on modern HRT guidelines. Many doctors aren't updated on recent evidence. Track symptoms for a month before appointments. Be specific about performance impacts. Don't accept "part of aging" as medical advice. Seek menopause specialists if needed.

The Technology Stack

Choose one wearable or app for hormonal health tracking. Initially, focus on sleep and recovery metrics. Look for patterns over three months. Upgrade to sophisticated tracking if basic data proves valuable. The goal is actionable insights, not perfect data.

The Competitive Edge Nobody Sees

Understanding female hormonal health creates massive advantages. Women who crack this code work with their physiology instead of fighting it. They prepare for transitions instead of being ambushed. They optimize systematically instead of suffering randomly.

The longevity implications are staggering. Decisions made during perimenopause affect the next 30-40 years. Bone density preserved now prevents fractures later. Muscle maintained now ensures future independence. Cardiovascular health protected now extends both lifespan and healthspan.

This connects directly to our Activate pillar because hormonal health is your biological baseline. You can't optimize systems you don't understand, and you can't work with biology you've never mapped.

The women in your life—daughters, partners, colleagues, employees—deserve better than myths and misconceptions. They deserve accurate information, effective treatments, and environments that help them thrive through every transition.

The Real Truth

Sometimes, I blast Taylor Swift in the car with my daughter and sing along at full volume. Maybe that's my hormonal response to her infectious joy. More likely, it's the simple pleasure of connecting through something she loves.

But watching her navigate the early stages of hormonal changes taught me something crucial: this isn't just women's health. It's human optimization we've been ignoring for decades.

The science is clear. The tools exist. The only thing missing is the conversation.

For too long, we've treated female hormonal health as a mystery to endure rather than a system to optimize. Whether you're raising a daughter, partnering with someone navigating menopause, or leading organizations filled with talented women, ignorance isn't an option anymore.

The performance variable we've ignored affects half the population. Time to pay attention.

Stay healthy.

Andre

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Research References Appendix

For readers interested in the specific studies cited:

"A 2020 systematic review analyzed 78 studies and 1,193 women"

Elliott-Sale, K.J., et al. (2020). "The effects of menstrual cycle phase on exercise performance in eumenorrheic women: a systematic review and meta-analysis." Sports Medicine, 51(7), 1479-1492. This comprehensive review examined exercise performance across menstrual cycle phases and found only trivial performance differences.

"The American College of Sports Medicine put it bluntly"

American College of Sports Medicine Position Stand on "The Female Athlete Triad" and related nutrition guidelines. ACSM emphasizes consistent daily energy and nutrient intake over cycle-based dietary manipulations, stating there is "no strong scientific evidence to suggest that female athletes should manipulate their dietary intake during different phases of the menstrual cycle."

"The Study of Women's Health Across the Nation tracked thousands of women"

Greendale, G.A., et al. (2019). "Changes in body composition and weight during the menopause transition." JCI Insight, 4(5). The SWAN study is a longitudinal multi-site study following women through the menopausal transition, documenting accelerated fat gain and body composition changes.

"The Women's Health Initiative study"

Writing Group for the Women's Health Initiative Investigators (2002). "Risks and benefits of estrogen plus progestin in healthy postmenopausal women." JAMA, 288(3), 321-333. The landmark study initially raised concerns about HRT risks in older postmenopausal women.

"Current medical consensus from leading organizations"

North American Menopause Society (2022). "The 2022 hormone therapy position statement of The North American Menopause Society." Menopause, 29(7), 767-794.

Endocrine Society Clinical Practice Guidelines on menopausal hormone therapy, emphasizing individualized risk-benefit assessment and favorable profiles for younger postmenopausal women.

These references provide the scientific foundation for this newsletter's claims. For those seeking deeper analysis, they are available through medical databases.

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A note for new readers:

I'm a trained reconstructive facial surgeon, medical doctor, and dentist. Before launching this newsletter, I had a varied career: competitive freestyle wrestler, management consultant (McKinsey), entrepreneur (Zocdoc, Thermondo, and docdre ventures), and corporate executive (Sandoz). Today, I'm a Managing Director and Partner at BCG.

Husband of one. Father of three. Split between Berlin's urban pulse and our Baltic Sea retreat. I'd rather be moving than sitting. Not just hobbies. Research. My body is my primary laboratory; I've been conducting experiments for decades.

If this is your first time here, welcome. I'm excited to share what I've learned—and will continue to learn—with you.

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DISCLAIMER:

Let’s get one thing straight: None of this—whether text, graphics, images, or anything else—is medical or health advice. This newsletter is here to inform, educate, and (hopefully) entertain you, not to diagnose or treat you.

Yes, I’m a trained medical doctor and dentist. No, I’m not your doctor. The content here isn’t a replacement for professional medical advice, diagnosis, or treatment.

If you have questions about your health, talk to your physician or a qualified health professional. Don’t ignore their advice or delay getting care because of something you read in Health, Redefined. Be smart. Do your research. And, as always, take care of yourself.