It has always been believed that the porters of Nepal are the strongest load-carriers on Earth. With a strap that goes across their foreheads to carry the weight, they lean forwards to balance their wickerwork baskets piled high with goods. They grunt and heave their way up and down the Himalayan trails for days on end. It had seemed superhuman, it apparently is.
The load-bearing capacity of the Nepali highlander has been recorded by more than one scientific team on the Everest trail up to the Sherpa market town of Namche Bazaar. The teams have studied the rugged men and women of Nepal's midhills who routinely carry loads that greatly exceed their own body weight to altitudes that would give any seasoned trekker pause. In a new study published in the academic journal Science, physiologist Norman Heglund and his colleagues from the Universite Catholique de Louvain in Belgium set out to determine exactly how the porters are able to carry so much.
Setting up a field research station near Namche Bajaar (height 3500 metres), the team examined over 100 male and female porters, chosen at random. The scientists determined the body weight and the weight of the loads carried by the selected porters, whose ages ranged from 11 to 68. Special masks were also used to monitor the oxygen intake of working porters as they climbed to reach the weekly Saturday bazaar at Namche.
On a single day before the Saturday market, the study counted more than 642 porters hauling an estimated 30 tons of freight up the steep climb from the Dudh Kosi valley. Most of these porters had traveled ten or more days by foot from the roadhead town of Jiri – logging more than 8000 metres of climbing and 6300 metres of descent. The average male porter on this route carried a load that amounted to 96 percent of his body weight, and female porters carried roughly 66 percent. The largest load observed was a whopping 183 percent of the carrier's body weight.