With Fallon Fox coming out as a transgender fighter, the age old debate about men being more dominant than women when going into a fight has started up again.
Although women have caught up in terms of strength and fight training, there are still differences in how both genders fight in terms of body type. The men are built with the ability to work with less fat and more muscle. While a healthy guy can run on 3-5% of body fat, women need at least 10-16%. So a man fighting at 135 pounds will have more muscle mass than a women the same size if both are in optimal range.
That fact works both ways, however. With more muscle mass, the body uses more oxygen and gassing out is more common in men than women.
Another fact is that women are more flexible then men, and are harder to submit in armbars and leglocks. You can argue that the armbar is the most common submission for women (Ronda Rousey and Megumi Fujii are famous for them) but if you look at the average times of women fending them off, they outshine the men by leaps and bounds. Flexibility also comes into play when it comes to positioning, including rubber guards and figure fouring the body more comfortably.
Men do have harder bones than women, but women’s flexibility enables them to kick higher and faster at times.
Pain threshold is also something the women have an advantage. On an episode of “Mythbusters” in 2010, an experiment showed that women outperformed their male counterparts when it came to keeping their hand in an ice cold bowl of water. This is also confirmed by a report in Time Magazine, which explained estrogen dulls pain receptors.
In this case, Fox is most likely on estrogen, which may dull her pain receptors but lowers her testosterone, which lessens muscle mass.
Ultimately, it is all about technique. Just as some fighters, male or female, are better in different aspects of the game (i.e. grappling or striking), it is using the tools you are given.