Do Sex Differences in Physiology Confer a Female Advantage in Ultra-Endurance Sport?
Level 5 - mechanism / opinion, no new human data
Narrative review synthesizing physiological mechanisms without systematic search methodology
PubMed 33502701 · doi:10.1007/s40279-020-01417-2
What was done
This narrative review synthesized literature on sex-based physiological differences to evaluate whether female athletes possess biological advantages in ultra-endurance sport (events exceeding 6 hours). The authors examined evidence across muscle morphology and fatigability, respiratory-neuromechanical function, substrate utilization, oxygen utilization, gastrointestinal structure and function, and hormonal regulation.
What was found
The abstract reports that the male-to-female performance gap narrows from ~10% in traditional endurance events (e.g., marathon) to as low as 4% in ultra-endurance competition, and females generally outperform males in extreme-distance swimming. Females display favorable phenotypes including greater fatigue resistance, higher substrate efficiency, and lower energetic demands, but these are counterbalanced by performance-limiting traits including lower oxygen-carrying capacity, higher prevalence of gastrointestinal distress, and sex-hormone impacts on cellular function and injury risk.
Why it matters
This paper clarifies the physiological mechanisms that may narrow the sex performance gap over extreme durations, identifying where female metabolic and muscular characteristics offer potential advantages and where cardiovascular constraints persist.
Limits
The abstract describes a narrative rather than a systematic review and does not provide sample sizes, search criteria, or study counts. Findings are also limited by low female participation rates in ultra-endurance events, which limits direct competitive comparisons.
Cited by
- supports As endurance race distances increase, the performance gap between male and female competitors narrows.