Well it is in the name, endurance RACES. It is a race not a test of pure endurance. To test pure endurance you would need to start running or walking or swimming at your own pace and continue till you drop to the ground and the one that can do that for the longest would have the best endurance.
There's a point at which women do tend to get better at endurance racing and often surpass men. And it's in the ultra long distance races. Which actually tracks, as hunting would have likely been a mix of long and ultra long distance running