Being petite is no excuse for not pulling your weight, according to new research.

Smaller backpackers can be better equipped to carry heavy loads than hulking hikers, a study has shown.

The reason may be linked to the fact that walkers carrying backpacks also have to haul their own body weight, scientists believe.

Hiking guidelines say that the weight of a pack should correspond to body size, with smaller individuals bearing lighter burdens.

Overall strength does not determine how heavy a backpack a person can comfortably carry

Michael O’Shea, a professor from Kansas State University, the US, who conducted the research using a computer model, said: “Online advice from several sources was somewhat misleading in suggesting that pack weight should be a certain per cent of a person’s weight.

However, as the size of any animal increases, strength increases more slowly than body weight – the reason why tiny ants can carry a disproportionately heavy load compared to their weight.

“Overall strength does not determine how heavy a backpack a person can comfortably carry.”

O’Shea was prompted to investigate the physics of backpacking after leading students on adventure trips. He noticed that some of the smaller hikers could carry greater back weights than larger students with similar fitness levels.

Incorporating pack weight and body proportion data, he came up with an equation to determine the maximum rucksack load suitable for a person of given size.

The research, published in The Physics Teacher journal, assumes that hikers being compared have similar levels of body fat.