Women in strength research: what we know and what is missing

Reviews of the exercise and sports science literature have repeatedly found that female participants are substantially underrepresented, with the majority of participants across studies being male. The gap is smaller than it was and it has not closed.

The commonly cited reason is that the menstrual cycle introduces a variable researchers must control for, which increases cost and complexity. Whatever the reason, the consequence is that a lot of advice is extrapolated.

What appears broadly similar

The good news first, because it is the larger part.

Relative strength gains. When expressed as a percentage of starting strength, women gain strength at broadly similar rates to men in response to resistance training.

Relative hypertrophy. Similar percentage increases in muscle size, from a lower absolute baseline.

The training principles. Progressive overload, adequate volume, proximity to failure, specificity — these apply the same way. There is no evidence supporting fundamentally different programming.

Protein requirements, broadly, when expressed relative to body mass or lean mass.

What appears to differ

Absolute strength, substantially, driven by differences in muscle mass, particularly upper body. This is unremarkable and it says nothing about trainability.

Fatigue resistance. Women tend to show greater resistance to fatigue at a given relative intensity, particularly in isometric and submaximal work. Several proposed mechanisms exist including muscle fibre composition and blood flow characteristics.

The practical implication, supported by some research, is that women may tolerate higher volumes and shorter rest periods, and may recover faster between sets. Some coaches use this to justify slightly higher rep ranges or more sets, and the evidence is suggestive rather than conclusive.

Substrate use. Women tend to oxidise proportionally more fat and less carbohydrate at a given relative intensity. The practical significance for resistance training is unclear.

Recovery from resistance training may be somewhat faster, though findings are mixed.

The menstrual cycle

The most-asked question and the one with the least settled evidence.

Hormonal fluctuations across the cycle are substantial, and theoretically they could affect strength, recovery, substrate use and injury risk.

The research is genuinely inconsistent. Some studies find performance differences across phases; many find none. A frequently cited review concluded that any effect of menstrual cycle phase on performance is likely small and highly variable between individuals, and that the quality of the underlying research is generally low.

Some work suggests periodising training to the cycle produces benefits; other work does not support it. The current honest position is that the evidence is not strong enough to recommend cycle-based programming universally.

What is better supported: individual variation is large. Some women experience marked symptoms affecting training in specific phases and some notice nothing. Tracking your own cycle alongside training performance for a few months gives you far better information than any general recommendation.

Hormonal contraception adds another layer and is itself under-studied.

Injury risk

Higher rates of anterior cruciate ligament injury in women in sports involving cutting and landing are well documented, with proposed contributions from anatomy, neuromuscular control and hormonal factors.

Neuromuscular training programmes reduce this risk substantially and have good evidence behind them. This is relevant to athletes; it is less relevant to resistance training itself, which is not a high ACL risk activity.

Areas of specific concern

Energy availability. Low energy availability has serious consequences including menstrual dysfunction and bone loss, and it is prevalent. Loss of menstrual function in a training woman is never normal and warrants medical assessment.

Bone health, particularly around and after menopause, where resistance training becomes more valuable rather than less.

Iron status, where deficiency is considerably more common than in men and is a frequent explanation for unexplained fatigue and poor training response.

Pelvic floor considerations, particularly postpartum, which are genuinely under-discussed and where specialist physiotherapy input is valuable and available.

The practical conclusion

Train the same way: progressive overload, compound movements, adequate volume, appropriate proximity to failure. The programming principles do not change.

Pay particular attention to eating enough, to iron status, and to bone-loading throughout life.

And treat the confident sex-specific training claims circulating online with the same scepticism you would apply to anything else — most of them are extrapolations from thin evidence, and some are the opposite of what the research suggests.