I appreciate what you are saying here but there are contradictions. It can be deduced that men can withstand more pain, and can endure more. This is often readily seen in real life scenarios. Examples would be things like army training, especially specific types of army units. Take for example infantry, para training, and rangers etc. The contradiction comes about because you have already pointed out that men will subject themselves to more initial pain. This comes in the form of selecting weights that are probably too much for them to endure reasonably. They are subjecting themselves to more initial pain. The women seem to endure more, but this is because they have not pushed themselves to the limit of pain, that men do. Therefore they can last longer... unless they are put to the test. Why is it that men will be well ahead of women in things like marathons? How many women can get through certain army training regimens? In a marathon, it is very rare for women to come in first, let alone second, or third, or... you get the picture. Men are stronger on average, but this also means they have a more densely muscular body, and hence a heavier body. When this comes to a marathon, it means more body mass to convey through an entire race, that is miles long.