Queensland researchers are calling for footwear manufacturers to design shoes specifically to support fallen arches in the increasing number of overweight and obese Australian children. A study released at a Brisbane medical conference has revealed the hips, knees and ankles of overweight children come under three times as much strain while walking, and the impact on the foot is worse still.
"We were able to show that all the extra weight bearing down was forcing fragile bones in the feet to move and the tiny ligaments to stretch out, creating a flatter arch," said lead researcher Dr Sarah Shultz, from the Institute of Health and Biomedical Innovation at the Queensland University of Technology.
"That creates foot pain and changes the way the kids move, ultimately making it more difficult for them to do the exercise they need to lose their extra weight."
Statistics show that 19 per cent of Australian children are overweight and a further six per cent are obese, with figures for both still increasing.
Dr Shultz collaborated with US researchers to study the impact on the joints in 22 American children aged between eight and 12.
Previous research has shown heavier children have flatter feet, but this was the first to objectively show it is caused by dropped arches, not just fat pockets on the bottoms of their feet.
"Many of the children were already suffering from foot and leg pain, but the greatest concern is what this pressure will do in the long term," she said.
"This doesn't bode well since they will need all the mobility they can get to burn that fat and lose weight."
Heavier children should be encouraged to do activities like swimming and biking, that don't stress the feet, and manufacturers should design shoes that suit the ever-increasing number of Australians with a lower arch, she said.
Past research has recommended other "custom built" equipment, from hospital beds and morgue benches to car seats and wheelchairs, that better cope with increasing weight in the population.
Professor Adrian Bauman, director of the Centre for Physical Activity and Health at the University of Sydney, said the effect of obesity on arthritis and muscular skeletal health was not taken seriously enough.
"The lifelong implications for quality of life are huge, but this is flying under the radar," Prof Bauman said.
