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Updated: Sep 13, 2025

Skeletal Muscle Gender Dimorphism from Proteomics
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Sex-differences in Mountain Ultra-trail Performance: Look at the Scenery.

Grégoire P Millet1, Alexa Callovini2,3, Antoine Raberin2

  • 1Institute of Sport Sciences, Faculty of Biology and Medicine, University of Lausanne, Lausanne, 1015, Switzerland. gregoire.millet@unil.ch.

Sports Medicine - Open
|July 27, 2025
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Summary
This summary is machine-generated.

Female athletes face greater challenges in mountain ultramarathons due to terrain, altitude, and temperature. These factors, including uphill-downhill locomotion and cold exposure, widen sex differences in ultra-endurance performance.

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Area of Science:

  • Exercise Physiology
  • Sports Science
  • Human Performance

Background:

  • Literature suggests female advantages in flat terrain ultra-endurance due to factors like higher type 1 muscle fibers and metabolic flexibility.
  • However, sex differences in performance are amplified in mountain ultramarathons compared to flat running events.

Purpose of the Study:

  • To identify and analyze specific factors contributing to larger sex differences in mountain ultramarathon performance.
  • To highlight the influence of mountainous terrain, altitude, and extreme temperatures on sex-based performance disparities.

Main Methods:

  • Review and synthesis of existing literature on sex differences in ultra-endurance exercise.
  • Analysis of physiological and environmental factors specific to mountain ultramarathon running.

Main Results:

  • Uphill-downhill locomotion shows greater sex differences (18-22%) than flat terrain (9-12%), linked to females' lower lean mass and fast-twitch fibers.
  • Altitude impacts females more due to sex-sensitive ventilatory responses and greater hypoxemia.
  • Cold environments pose greater challenges for females due to lower muscle mass, higher surface-area-to-mass ratio, and Raynaud's phenomenon prevalence.

Conclusions:

  • Specific factors in mountain ultramarathons—uphill-downhill movement, altitude, and extreme temperatures—significantly widen performance sex differences.
  • Further research is needed to fully understand these sex-specific physiological responses in mountain ultra-trail running.