Energetic cost of carrying loads: have African women discovered an economic way?

@article{Maloiy1986EnergeticCO,
  title={Energetic cost of carrying loads: have African women discovered an economic way?},
  author={G. M. O. Maloiy and Norman C. Heglund and Laura M. Prager and Giovanni A. Cavagna and C. Richard Taylor},
  journal={Nature},
  year={1986},
  volume={319},
  pages={668-669}
}
When travelling in East Africa one is often surprised at the prodigious loads carried by the women of the area. It is not uncommon to see women of the Luo tribe carrying loads equivalent to 70% of their body mass balanced on the top of their heads (Fig. 1). Women of the Kikuyu tribe carry equally large loads supported by a strap across their foreheads; this frequently results in a permanently grooved skull. Recent experiments on running horses, humans, dogs and rats showed that the energy… 
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N o ‘ free ride ’ for A fricAN womeN : A compArisoN of heAd - loAdiNg versus bAck - loAdiNg AmoNg X hosA womeN
Although contrasting evidence exists in the literature as to the economy of head-loading, there is a notion that head-loading is an extremely economical method of load carriage. This has become known
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