Thanks to the majority-male data informing consensus positions on resistance training.
It’s been traditional in medicine to treat women as undergrown men, with excellent results. It seems that applies at the gym as well.
Lifting weights may once have been a largely male preserve, but not any more: the benefits for muscle strength and bone density, joint health, balance, flexibility and mood are too well known – especially in mitigating the effects of menopause – for women not to have got in on the act.
But the overwhelming majority of data on which resistance training guidelines are based are still from studies on males, conducted by males, according to a study from the University of NSW, published in Sports Medicine.
Researchers took consensus statements from governing bodies around the world such as the Australian Strength and Conditioning Association (who knew?) and analysed their source material authors and study populations.
(The team uses “female” when talking about biological sex and “women” when denoting gender, acknowledging that neither sex nor gender is binary and that some subjects may have been accidentally misclassified.)
While consensus statements specialise by age and even by chronic disease, the authors say, one is yet to be developed that specifies the best resistance training regime by sex.
Females are not in fact smaller, weaker males, they remind us: “Between sexes, physiological differences in body fat percentage and distribution, oxygen-carrying capacity, metabolic responses and biomechanics may result in marked differences in response to and recovery from RT. Females also differ across the lifecycle with influences of the menstrual cycle, menopause and pregnancy altering physiology and the associated benefits of RT.”
They identified 11 guidelines published 2004-11, using 1562 studies in which subject sex data was reported.
For youth guidelines, study participants were 70% male overall. While 287 studies recruited males and females (subjects were 73% male), 205 studies were male-only and 92 female-only.
For adults, study participants were again 70% male overall. This time the majority of studies, 204, were male-only, with 104 recruiting both sexes (with 63% of subjects being male) and 44 females only.
Only for older adults were the proportions more equal, with 54% of participants being female. Here there were 395 studies that recruited both sexes, 112 male-only studies, and 83 female-only studies.
The authors of this study say the reason for the disparities in youth and adult populations are unclear: while participation rates have traditionally been lower for women, that is changing, they say, citing an Australian survey in which women were more likely than men to report muscle-strengthening activities over the previous 12 months.
The relative sex balance in the older adult population also can’t be explained by this study, though the authors suggest this may be due to females living longer than males – so there are more of them to study.
As to the authors of the position statements, 85% were men, and 91% of lead authors were men. This balance did not improve over the two-decade scope of the study.
“While there is a need for single-sex study designs to address some research questions,” the authors conclude, “there is specifically a dearth of high-quality literature relating to female exercise physiology. Further, there is still much to be learned regarding sex differences in exercise responses. Simple steps such as sex-disaggregation of data when conducting studies including both sexes will help reduce this gap and progress the field.”
They also have a stern word for the people writing the consensus statements: “We encourage authors of these types of statements to be cognisant of the data that they are using to draw their inferences, and where data are not inclusive of both sexes, state this clearly in the review so the reader is able to interpret for themselves.”
