The question of whether women have stronger legs than men requires separating strength into distinct scientific definitions. While men generally possess greater total muscle mass, translating to a higher capacity for overall force production, this does not mean women’s legs are inherently weaker across all metrics. The differences depend entirely on whether strength is measured in absolute terms or relative to factors like body size or lean tissue. Biological disparities, which become pronounced after puberty, influence the structure and function of the lower body, leading to unique performance profiles.
Absolute Strength Versus Relative Strength
The primary difference in strength between sexes is seen when measuring absolute strength—the total amount of force an individual can generate. On average, men exhibit greater absolute lower-body strength than women; women’s strength typically falls in the range of 60% to 80% of men’s in untrained populations. This disparity is largely due to men having a greater amount of total lean mass and a larger muscle cross-sectional area (CSA) in the lower limbs. For example, women’s quadriceps CSA is often 70% to 80% that of men’s, which limits maximum force output.
The picture changes significantly when considering relative strength, which normalizes force production to body metrics. When strength is measured relative to body weight, lean body mass (LBM), or muscle CSA, the strength differences narrow considerably. Studies show that when lower-body strength is normalized to muscle CSA, there is no significant difference in the quality of the muscle tissue between men and women. In these relative terms, the strength capabilities of the muscle fibers are comparable, indicating the strength gap is primarily a function of muscle quantity, not muscle quality.
Physiological Factors Influencing Lower Body Strength
The biological basis for differences in muscle mass and absolute strength begins during puberty, driven primarily by sex hormones. Testosterone, present at significantly higher levels in men, promotes greater muscle protein synthesis and leads to a substantial increase in muscle mass. Women have much lower levels of testosterone and higher estrogen levels, contributing to a greater percentage of body fat and less overall muscle mass. This hormonal divergence results in the larger muscle CSA observed in men, which is directly correlated with higher absolute strength.
Muscle fiber composition also influences functional strength differences in the lower body. Women tend to have a greater proportional area of Type I, or slow-twitch, muscle fibers, which are highly resistant to fatigue and optimized for endurance. Men generally have a greater proportion of Type II, or fast-twitch, muscle fibers, built for rapid, powerful contractions and higher absolute force production. This difference means that while men may have an advantage in explosive power, women often demonstrate a superior capacity for sustained, sub-maximal contractions, explaining why women frequently show greater lower-body muscular endurance than men.
Biomechanical Advantages and Functional Performance
Functional performance in the lower body is also shaped by differences in skeletal structure and biomechanics. Women typically have a wider pelvis, resulting in a greater Q-angle—the angle formed by the thigh bone and the shin bone at the knee. This wider angle can affect the alignment of the knee joint and the mechanics of movement. The altered geometry can lead to greater non-sagittal plane movement, including increased hip adduction and internal rotation, which requires different muscle activation patterns for stability.
The structural differences also influence injury risk, with women having a higher incidence of certain lower-body injuries, such as anterior cruciate ligament (ACL) tears. This heightened risk is often linked to the combination of a wider Q-angle and differences in neuromuscular control, particularly a relative lack of strength in the muscles that stabilize the knee. Despite these biomechanical considerations, the greater prevalence of slow-twitch fibers and efficient substrate utilization gives women a functional advantage in lower-body muscular endurance. This ability to resist fatigue translates to stronger performance in activities requiring sustained effort, even if the absolute strength capacity is lower.