A study on the combined effect of obesity and load carriage on plantar pressure patterns of primary school children

From childhood, children are required daily to carry a load (necessary to perform their regular school activities) that is often beyond the limits established for adult workers. While some critical issues related to possible negative consequences in terms of postural alterations and onset of musculoskeletal diseases are well known and investigated, little information is available for the population of overweight and obese children, which appears to increase year after year. As their bodies are physiologically subject to a certain degree of overload, the addition of a supplemental load may induce further stress, the effects of which should be carefully evaluated. This study focuses on the foot-ground relationship, with special attention on plantar pressure distribution. The primary goal is to assess whether or not backpack presence alters in different ways the physiological pressure patterns in obese subjects compared with normal ones. To this end, 45 obese and overweight children (6-10 years old) and an equal sample of non-obese schoolmates matched for gender, age and height, were tested with a pressure platform to acquire the plantar pressure distribution in absence and presence of a backpack. Results show that the carried load induces similar increases in both groups, even though a significant shift of the center of pressure in presence of a backpack was found for obese female subjects. The very high pressure peaks observed in the obese population suggest that further studies are required to evaluate specific issues of the musculoskeletal system related to the combination of load carriage and obesity.