She has directed research programs at Stanford, AUT University, and the University of Waikato, focusing on female athlete health and performance and pushing the dogma to improve research on all women.

With the unique opportunities Silicon Valley has to offer, during her tenure at Stanford, she had the opportunity to translate earlier research into consumer products and a science-based layperson's book (ROAR) written to explain sex differences in training and nutrition across the lifespan. Both the consumer products and the book challenged the existing dogma for women in exercise, nutrition, and health. This paradigm shift is the focus of her famous “Women Are Not Small Men” TEDx talk.

Her contributions to the international research environment and the sports nutrition industry have established a new niche in sports nutrition and solidified her reputation as the expert in sex differences in training, nutrition, and health.

She has published over 100 peer-reviewed papers and several books and is a regularly featured speaker at professional and academic conferences.

Stacy currently holds a Senior Research Associate position with SPRINZ–AUT University, an adjunct position with the Stanford Lifestyle Medicine Group, supervises PhD students, writes academic papers, and is on the advisory board of several cutting-edge companies.

On www.drstacysims.com, she creates and delivers online learning material focused on women training with their physiology across the lifespan.