Prehistoric women's arms 'stronger than those of today's elite rowers'

Prehistoric women had stronger arms than elite female rowing teams do today thanks to the daily grind of farming life, researchers have revealed, shedding light on their role in early communities.

The study of ancient bones suggests that manual agricultural work had a profound effect on the bodies of women living in central Europe between about the early neolithic and late iron age, from about 5,300BC to AD100.

“We think a lot of what we are seeing is the bone’s response to women grinding grain, which is pretty much seated but using your arms really repetitively many hours a day,” said Dr Alison Macintosh, co-author of the research from the University of Cambridge.

The study also reveals that the strength of women’s arm bones dropped over time – probably as technology was developed to ease manual labour. By medieval times, the strength of women’s arm bones was on a par with that of the average woman today.

The research builds on previous work by the team on male leg bones, which revealed a decline in strength since the late iron age. “Early farming men had these really strong leg bones – when you compared them to living men they were close to what you see in living runners, suggesting they were really active,” said Macintosh. “Then [there is] this really progressive decline though time in bone strength, down to what you see in living sedentary undergraduate students at Cambridge.”

With similar trends not seen for women, Macintosh and colleagues decided to explore whether skeletal remains could offer other clues about the roles of women in early farming communities. To do so they explored the remains of 94 women spanning about 6,000 years, from the time of the early neolithic farmers (dating back to around 5,300 BC) through to the 9th century, from countries including Germany, Austria, and northern Serbia.

In addition, the team looked at scans from bones of 83 living women who fell into four groups: runners, rowers, footballers and those who were not particularly sporty.

The researchers explored the strength of two bones: the tibia, or shin-bone, and the humerus – the long bone in the upper arm.

Comparing between bones of women across the ages rather than between the sexes was crucial, said Macintosh, explaining why the team did not look at male arm bones. “Men put more bone on, and in a stronger way, in response to physical activity than women do, even if those activities are really similar,” she said. The study also notes that comparisons with modern women can also present problems – for example, that hormonal contraceptives can affect certain bone properties.

The results, published in the journal Science Advances, reveal that while the arm bones of women from the neolithic to the late iron age showed variations in strength, they were stronger than those of rowers, football players, and non-athletic women for their left arm, and the latter two groups for their right. Indeed, the neolithic women had arm bones about 30% stronger than non-athletic living women.

“We really saw them standing out through that first 5,500 years of farming, just really consistently stronger arm bones than the majority of the living women, including the rowers,” said Macintosh. “Medieval women had much weaker arm bones than those previous prehistoric women; they looked a lot more like modern, recreationally active women.”

While grinding grain using stone tools was likely to be a key factor in boosting women’s bone strength, the researchers add that other strenuous occupations including pottery making, planting and harvesting crops, and tending livestock could also have contributed.

The findings, said Macintosh, throw a spotlight on the hard graft of women and their role in farming communities.

“Women have been doing rigorous labour over thousands of years [and] that’s really been underestimated so far because we haven’t been comparing them to living women,” she said. “It’s highlighting those hours of work that women have been doing that have been hidden in the archaeological record until now.”