Higher testosterone in men leads to greater muscle mass, haemoglobin, bone size and cardiac output, explaining much of the performance gap between sexes, while female physiology confers advantages during prolonged submaximal exercise, resulting in a persistent performance gap of around 10%-15% in most sports that narrows as event duration increases.
A persistent performance gap of approximately 10%-15% exists between sexes in most sports, particularly those requiring strength and power.
Higher testosterone in men drives greater muscle mass, haemoglobin concentration, bone size, and cardiac output, explaining much of the sex-based performance difference.
Female physiology confers advantages during prolonged submaximal exercise through greater fat oxidation, lower carbohydrate dependence, and improved fatigue resistance.
Sex differences influence risk of exercise-related pathology, including reproductive dysfunction such as hypothalamic amenorrhoea.
Sex differences in exercise physiology have clinical implications for sports medicine and endocrinology, emphasizing sex as a fundamental biological variable.
This review paper examined the biological reasons why men and women differ in physical performance and susceptibility to exercise-related health problems. By analyzing data primarily from human studies, the researchers found that male sex hormones, particularly testosterone, drive well-known physical advantages in men including larger muscles, higher red blood cell counts, bigger bones, and a greater heart output — all of which contribute to a roughly 10–15% performance gap favoring men in most sports, especially those involving strength or explosive power. However, this gap becomes smaller in very long-duration events like ultra-marathons. The research also highlights that women have their own physiological advantages during prolonged, lower-intensity exercise. Women's bodies are better at burning fat for fuel, rely less on carbohydrates, and show greater resistance to muscle fatigue — factors that may help explain why female athletes perform relatively closer to male athletes in ultra-endurance competitions. Additionally, the review found that sex influences how people respond to training and their risk for specific health problems, including reproductive disruption (such as loss of menstrual periods due to heavy training), certain musculoskeletal injuries, and differences in how the body regulates temperature during exercise. This research suggests that sex is a fundamental biological variable that should be considered in both sports science and clinical medicine. The findings have practical relevance not only for competitive athletes but also for people working in physically demanding occupations. Recognizing and accounting for these biological differences could improve training programs, injury prevention strategies, and medical care tailored to the specific needs of male and female individuals.
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Upload Your LabsHoldsworth D, O'Leary T, Doig C, Taylor N, Dosanjh J, Woods D, et al.. (2026). Physiological Basis of Sex Differences in Human Performance and Exercise-Associated Pathology.. Clinical endocrinology. https://doi.org/10.1111/cen.70150