In episode #178, we spoke with Dr. Trent Stellingwerff and Susan Boegman and look inside a landmark study on female ultra endurance athletes, featuring unprecedented data on its participants. Discover how energy expenditure, nutrition, biomechanics, and recovery strategies come together in one of the most comprehensive multi-disciplinary studies in endurance sports.
In this episode:
- Overview of the six-day ultra marathon study involving 10 women from diverse backgrounds
- How energy intake and expenditure are measured with gold-standard methods like doubly labeled water and metabolic tracers
- The physiological and psychological effects observed during extended endurance events
- Unique findings on body composition changes, neuromuscular fatigue, and hydration dynamics
- Why field-based research offers higher ecological validity compared to laboratory settings
- Implications for athletes, coaches, and sports scientists supporting ultra endurance performance
Resources & Links:
- More about the study:
- Defining Taining and Performance Caliber: A Participant Classification Framework: https://journals.humankinetics.com/view/journals/ijspp/17/2/article-p317.xml
- Oura Ring: https://amzn.to/4c0Tdjx
- Lululemon Puffer Jacket: https://go.shopmy.us/p-50748716
Connect with the Researchers:
- Trent Stellingwerff:
- LinkedIn: https://www.linkedin.com/in/trent-stellingwerf/
- Google Scholar: https://scholar.google.com/citations?user=73zEx-QAAAAJ&hl=en
- Upcoming Speaking Engagements:
- American College of Sports Medicine Conference, May 2026: https://acsm.org/events-general/annual-meeting/
- International Society of Sport Nutrition, June 2026: https://www.sportsnutritionsociety.org/
- Susan Boegman – CSIP
Timestamps:
00:00 – Introduction to the innovative six-day ultra marathon study
00:45 – Participants’ demographics and athlete classification system
02:10 – The multi-disciplinary research team and their roles
03:15 – Study design: field-based versus lab-controlled research
04:00 – Key research questions: energy balance, body composition, and fatigue
05:20 – Measuring energy intake: food weighing, wrappers, and meal support
06:45 – Using doubly labeled water and other methods to assess energy expenditure
08:10 – Unique focus on female ultra athletes and physiological insights
09:55 – Participant goals and athlete motivation during the event
11:15 – Environmental conditions: terrain, temperature, and altitude
13:05 – Challenges posed by weather, location, and logistical adjustments
15:10 – Nutritional strategies: supporting athletes with diverse dietary preferences
16:55 – Impact of hydration and water retention on body weight and performance
18:30 – Neuromuscular fatigue and muscle recovery observations
20:00 – High-energy expenditure records: the case of Camille Herron
21:45 – Menstrual cycle considerations and hormonal factors
23:30 – Ensuring athlete safety and medical support during the race
26:00 – Key takeaways: energy deficits, performance metrics, and future research directions
28:45 – Wrap-up and when to expect the upcoming published papers
This deep dive into ultra endurance research highlights the complex interplay of physiology, nutrition, psychology, and environment. It offers valuable insights for anyone interested in pushing human limits sustainably and safely.
Pushing Limits: Inside a Landmark Study on Female Ultra Endurance Athletes.
