But Macintosh says that’s not all that contributed to their strength. They also fetched water, milked cows, and converted hides and wools into clothing. In fact, when the researchers compared the tibial (leg) bone strength among modern, living women and prehistoric bone remains, they found a wide range. Some prehistoric women had the legs of elite distance runners, while others’ looked more like those of sedentary college students. This suggests, says Macintosh, that there was a wide variability in what women in those societies did.