Apparently biology makes a difference.
[[https://www.bbc.co.uk/news/uk-wales-51434749 Rugby concussion: Swansea University study into protecting women
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Because women rugby players tend to get knocked heads in a different way to men players, and because women's brain cell fibres appear to be constructed differently and be more fragile than men's, leading to women being more vulnerable to concussion and with worse effects than for men, Swansea University has decided on a radical approach for the women's squad:
"...we train them as women and not as small men."