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womens physiology & nutrition Expert
Guidance from Stacy T. Sims.Every day.
International exercise physiologist and nutrition scientist behind the 'Women Are Not Small Men' paradigm shift in female-specific training and nutrition; author of ROAR and Next Level.
Stacy T. Sims
Exercise Physiologist & Nutrition Scientist, SPRINZ – AUT University
Stacy T. Sims, MSc, PhD, is an international exercise physiologist and nutrition scientist who specializes in sex differences in training, nutrition, and health across the female lifespan. She holds a Senior Research Associate position with SPRINZ at AUT University in New Zealand, and has directed research programs at Stanford University, AUT University, and the University of Waikato focused on female athlete health and performance. She earned her sports science degree at Purdue University, a master's in exercise physiology at Springfield College, and her PhD at the University of Otago. A former professional cyclist and triathlete who raced Ironman Kona and the XTERRA World Championships, she co-founded Osmo Nutrition in 2012, translating her Stanford research into sex-specific hydration products. Her 2019 TEDx talk 'Women Are Not Small Men' catalyzed a paradigm shift in the science of nutrition for women, and her books ROAR (revised 2024) and Next Level (2022, with Selene Yeager) bring female-specific training, nutrition, and menopause physiology to a general audience. She has published more than 100 peer-reviewed papers and serves on the advisory boards of Tonal Strength Institute, WILD.AI, and EXOS.
Exercise Physiologist & Nutrition Scientist, SPRINZ – AUT UniversityStacy T. Sims
Areas of expertisewomens physiology, nutrition, training, endurance, menopause
2 published booksROAR, Revised Edition: Match Your Food and Fitness to Your Unique Female Physiology, Next Level: Your Guide to Kicking Ass, Feeling Great, and Crushing Goals Through Menopause and Beyond
7 works in the Ottavia corpusApplied to your guidance with attribution
over7publications
Expert knowledge, applied to your day.
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How Ottavia and Stacy T. Sims work for you
Understand your body.
Ottavia recognizes patterns across your sleep, recovery, activity, nutrition, and lifestyle.
Know what to do next.
Every recommendation combines your health data with the expertise you trust.
Everything included with your subscription
The full Ottavia app, with Stacy T. Sims's knowledge applied to every report, question and log.
Reports that explain, not just summarize.
Sleep, recovery, workouts, weight, blood pressure, and more. Each report connects your health data, habits, and personal context to uncover what matters most. Instead of overwhelming you with numbers, Ottavia highlights the patterns, explains why they matter, and helps you make better decisions.
Daily Reports
Start every day with clarity.
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Expert guidance for every decision.
Food Guidance
Know what to eat and why.
Adaptive Plans
Plans that evolve with you.
Smart Nudges
Helpful guidance at the right moment.
Your health tools, connected.
Enjoy connecting your favourite wearables, devices and apps to discover health patterns
COMING SOONThe future of personalized health
Health isn't built in a day. It's built through years of small decisions, changing bodies, and evolving needs.
Built to grow with you.
Every day adds another piece to your health story. Over time, Ottavia connects your wearables, biomarkers, blood tests, symptoms, habits, and life events to uncover patterns unique to you.
Built by woman for woman
Women's health isn't a niche. From menstrual health and pregnancy to perimenopause and healthy aging, Ottavia is built to understand the biological changes that shape women's lives.
Your personal board of experts
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Free
Educational, not medical advice. Subscription happens in the Ottavia app.
How does it work?
Connect your wearable or log your sleep, meals and workouts. Each morning Ottavia reads your night and your day, applies Stacy T. Sims's methods where they fit, and gives you one clear plan. Ask anything during the day; the answers use your own data.
What do I get with Stacy T. Sims's subscription?
Their published methods and research, applied by Ottavia to your own sleep, training and meals every day. You see where their work shaped a message, every time.
Why can't I get this from ChatGPT?
ChatGPT answers from general knowledge and forgets you between questions. Ottavia reasons from your actual data, every day, and applies a named expert's published method with attribution. It is not advice in general; it is about your Tuesday night.
Is this medical advice?
No. Stacy T. Sims guides and educates through Ottavia. They never diagnose or prescribe.
Do I talk to Stacy T. Sims directly?
No. Ottavia has read their published work and applies it inside your guidance. Your questions go to Ottavia; their thinking comes back in the answer, attributed.
What happens to my health data?
Your data stays in your Ottavia account and is used only to guide you. AI runs on anonymized context, separated from your identity; your personal and health data is never shared with any AI provider, and never sold.
Does Stacy T. Sims see my data?
No. Experts contribute their methods to Ottavia; they never see individual users or their data.
Do I need a wearable?
Ottavia works best with Apple Watch, Garmin or Google Health. You can also log sleep, meals and workouts yourself.
What does it cost, and can I cancel?
The price is shown clearly before you subscribe. Manage or cancel anytime in the Experts hub; you keep access until the end of the period you paid for.