Stacy Sims, 'Women Are Not Small Men,' Now Has a Startup

For most of her career, Dr. Stacy Sims has made one argument in one form or another: sports and nutrition advice built on studies of men doesn’t work for women. Her best-known version is a 2019 TEDxTauranga talk called “Women are not small men.” In October 2026 she turned it into a company. Collective X Health, which she co-founded with CEO Lindsey Abramo and Angelica Marden, came out of stealth on October 13 with an oversubscribed $3.2 million pre-seed round. The SaaS News lists all three as founders.

Two decades of the same argument

Sims is an exercise physiologist and nutrition scientist. Per Wikipedia’s summary of her career, she earned a sports science degree from Purdue in 1995, a master’s in exercise physiology and metabolism from Springfield College, and a PhD from New Zealand’s University of Otago in 2006, with a thesis on how men and women respond to sodium loading. She founded Osmo Nutrition in 2012, formulated a rehydration drink for the Garmin-Slipstream cycling team, and is listed as adjunct faculty with Stanford’s Lifestyle Medicine group and a research associate at Auckland University of Technology.

Her public reach comes from two books written with journalist Selene Yeager: ROAR (2016, revised in 2024), on adapting training and nutrition to female physiology, and Next Level (2022), on training through menopause.

What Collective X Health does

The company is a data layer, not a consumer app. Per Femtech Insider, it turns peer-reviewed research and female-specific data into a structured, auditable research base that companies license through an API, with every claim citing its source. Customers can use it as their women’s health research foundation or to check their own findings. The intended buyers are wearable makers, digital health platforms, performance brands and sports teams. Its first two are Human Powered Health and Altra Running.

Sims leads the Research Lead Collective, the group of clinicians and scientists who vet what goes in. “Women have been systematically excluded from health research, with generational consequences,” she said in the launch announcement.

Abramo’s pitch is aimed at the companies already selling to women: “Every company claiming to serve women should be able to show the research behind that claim.” She also says that less than 9% of NIH funding reflects women’s health. That’s her figure, quoted by Femtech Insider, and we haven’t checked it against NIH’s own data.

Elizabeth Davis of the Anthemis Female Innovators Lab Fund explained why she invested: “Collective X’s edge isn’t a smarter model. It’s a smarter foundation underneath the model.”

A researcher becomes a founder

Collective X Health is small and early. The company hasn’t published revenue or how many customers it has beyond the two named. What it has is the thing most women’s health startups have to borrow: a scientist with a public following whose name is already attached to the research.

Sims isn’t the first athlete-scientist on this site to turn expertise into a product. Elizabeth Stein was a holistic nutrition coach and triathlete when she started Purely Elizabeth, which Ferrero agreed to buy in 2026. Val Emanuel built Rif Care after her own hormone crisis, another founder who started from the gap in what women were told about their own bodies. Sims is selling something less visible than either: the evidence that other women’s health products are supposed to rest on.

Sources: Femtech Insider (October 13, 2026), Wikipedia. Last checked October 28, 2026.