Stacy Sims

Stacy Teresa Sims (born 1973) is an American exercise physiologist, nutrition scientist, author, and women's health and fitness advocate. A former bike racer and triathlete, she holds positions at Stanford University in the United States and at Auckland University of Technology in New Zealand and writes and speaks on best exercise and fitness practices for women.

Early life and education

Born into an American military family, Sims spent much of her childhood in the Netherlands, was in a French immersion elementary school program, and received her high school education in San Francisco. She pursued ballet until she was 13, when she concentrated on running, competing in cross country running and field hockey in high school. She earned a sports science degree from Purdue University in 1995 after changing her major from political science, and instead of cross country running, competed in rowing while running for fitness, including multiple marathons. She completed a master's degree in exercise physiology and metabolism at Springfield College, where she was a member of an ultrarunning group, and after moving to New Zealand for the first time in the 1990s, a PhD at the University of Otago in 2006.

From 2007 to 2012, Sims was a research associate studying sex differences in physical activity, performance and health at Stanford University, and she has also held a research position at University of Waikato.

Athletic career

Sims was a bike racer for UCI Team Tibco and triathlete. She has competed in the Ironman Kona and the Maui Xterra World Championships.

Career in physiology

Sims' experiences training as an athlete, and the lack of research into how women should eat and exercise for both fitness and performance, led her to focus on women in her graduate studies and professionally, adopting the motto "Women are not small men." As of February 2026, she holds a research associate position at Auckland University of Technology. and an adjunct faculty position as an exercise physiologist and nutrition scientist with the Stanford Lifestyle Medicine group, part of the Stanford Prevention Research Center at Stanford Medical School. She formulated a low-carbohydrate rehydration drink for the Garmin-Slipstream cycling team, Secret Drink Mix, which was marketed by team nutritionist Allen Lim, and in 2012 she founded Osmo Nutrition.

Sims writes and is interviewed widely. She became a monthly columnist for Ella Cycling Tips in 2015, delivered a talk titled "Women are not small men" at TEDxTauranga in 2019,, and has published two books on fitness for women: ROAR in 2016 and Next Level in 2022, both co-authored with Selene Yeager. Her advice on exercise and nutrition for women is widely quoted.

Personal life

Sims is married and has a daughter; she lives in New Zealand.

Books

References

  1. 1 2 3 4 5 6 7 8 9 Tilton, Morgan (April 11, 2024). "'Women Are Not Small Men:' Dr. Stacy Sims and the Women's Endurance Sports Revolution". iRunFar. Archived from the original on February 11, 2025. Retrieved May 21, 2026.
  2. 1 2 3 May, Margaret (May 29, 2025). "Stacy Sims, 50: Taking Up Space". Ageist (interview). Retrieved May 21, 2026.
  3. ↑ Sims, Stacy Teresa (2006). Plasma volume and the physiological response to sodium loading in men and women. School of Physical Education (PhD thesis). Dunedin: University of Otago. OCLC 173284527. Archived from the original on February 6, 2016.
  4. 1 2 3 Perkins, Rachel (January 30, 2020). "Book Review: 'ROAR: How to Match Your Food and Fitness to Your Female Physiology for Optimum Performance, Great Health, and a Strong, Lean Body For Life' by Stacy Sims, Ph.D". FasterSkier. Archived from the original on February 11, 2025. Retrieved May 21, 2026.
  5. 1 2 3 Sims, Dr. Stacy (August 16, 2015). "Women are not small men: How gender dictates nutritional needs during training and recovery". Velo Outside (Introduction by Jessi Braverman). Retrieved May 21, 2026.
  6. 1 2 3 4 "Women are not small men says scientist". Bay of Plenty Times. March 15, 2019. Archived from the original on February 28, 2025 – via The New Zealand Herald.
  7. 1 2 Blacking, Deena (March 6, 2023). "Seven ways 'traditional' cycle training approaches don't work for women - and what you can do instead". Cycling Weekly. Archived from the original on February 11, 2025. Retrieved May 21, 2026.
  8. ↑ Lidbury, Emma-Kate (November 24, 2020). "2020's Multisport Movers and Shakers: Stacy Sims". Triathlete. Archived from the original on March 20, 2023. Retrieved February 11, 2025.
  9. 1 2 Millar, Abi (May 7, 2026). "Do women need to exercise differently from men – and ease up on cardio after 40?". The Guardian. Retrieved May 21, 2026. You might say that Stacy Sims is to women's exercise what Dr Chris van Tulleken is to ultra-processed foods: changing the conversation almost single-handedly while undaunted by any pushback.
  10. ↑ "Leading nutrition expert: Why women should think about ageing well, not losing weight". The New Zealand Herald. September 13, 2024. Archived from the original on February 11, 2025. Retrieved May 21, 2026.
  11. ↑ Nelson, Monica; Thorpe, Holly; Wheaton, Belinda; Clarke, Gloria Hinemoa; Sims, Stacy (February 19, 2026). "Eternal Wound, Performance Enhancement, or Minor Inconvenience?: Managing the Menstrual Cycle in Olympic Weightlifting". Journal of Sport and Social Issues (co-author biography). doi:10.1177/01937235261424379.
  12. ↑ "Our Team". Stanford Lifestyle Medicine. Retrieved May 21, 2026.
  13. 1 2 Gulley, Aaron (November 7, 2013). "Stacy Sims's War on Sports Drinks". Outside. Retrieved May 21, 2026.
  14. ↑ "Osmo Female Leaders Featured in Triathlete Magazine". Osmo Nutrition. March 2024. Retrieved May 21, 2026.
  15. ↑ Smith, Candace Cordelia (August 16, 2022). "CEO Corner: Dr. Stacy Sims Translates Science For the Betterment of Women's Health". Athletech News (interview). Retrieved May 21, 2026.
  16. ↑ Beddington, Emma (November 7, 2024). "'My upper arms are like jelly': can I learn to love weightlifting in six weeks?". The Guardian. Retrieved May 21, 2026. I ask Dr Stacy Sims – an exercise physiologist and the high priestess of midlife strength.
  17. ↑ Wilkins, Bridie (February 11, 2025). "4 life-changing lessons from the world's best studies on exercise for women, by a female physiologist". Women's Health. Retrieved May 21, 2026.
  18. ↑ "This expert just shattered the fitness rules women have followed for decades". Stuff New Zealand. April 7, 2025. Retrieved May 21, 2026.
  19. ↑ Bradfield, Hannah (November 14, 2025). "Why 'true high-intensity' cardio, like sprinting, is essential for women over 40 – and the best workouts to do". Runner's World. Retrieved May 21, 2026. Also at Women's Health, November 10, 2025.
  20. ↑ Oehlmann, Gabrielle (January 3, 2026). "Coach: A lot of women do this each morning - but it's likely causing more stress than we realise". Nine.com.au. Retrieved May 21, 2026.
  21. ↑ Storr, Kat (March 27, 2026). "Exercise scientist reveals the strength training mistake many women make, even after lifting for years". Women & Home. Retrieved May 21, 2026.
  22. ↑ Raby, Julien (May 12, 2026). "This Stanford PhD Reveals Why Lifting Heavy Weights 3x a Week Rewires Your Brain During Menopause (It's Not About Muscle)". Boxlife. Retrieved May 21, 2026.