Lower activity levels are related to higher plantar pressures in overweight children

This study aimed to establish whether the peak plantar pressures generated by overweight and obese school-age children during walking were associated with their objectively measured physical activity.

Physical activity levels of a subset of 73 overweight/obese children from a randomized controlled trial (mean ± SD: age, 8.3 ± 1.1 yr; 47 girls; body mass index z-score, 2.7 ± 0.7) were objectively measured using accelerometers. Plantar pressure distributions were also quantified as the participants walked over a pressure platform. Pearson product moment correlation coefficients were calculated to determine the strength of the relations between the peak plantar pressures generated during walking and the physical activity levels for overweight/obese children.

Peak pressures generated beneath the forefoot during walking were inversely correlated with time spent in different intensity levels of physical activity. Moderate-intensity (r = -0.321, P = 0.007), vigorous-intensity (r = -0.326, P = 0.006), and moderate- to vigorous-intensity (r = -0.342, P = 0.004) physical activity were significantly correlated with middle forefoot pressure and with lateral forefoot pressure (r = -0.248, P = 0.040; r = -0.264, P = 0.028; r = -0.267, P = 0.027, respectively). Lateral midfoot (r = -0.244, P = 0.044) and second toe (r = 0.227, P = 0.021) pressure were also significantly correlated with vigorous-intensity activity.

Those children who generated higher pressures beneath their forefoot and midfoot during walking had lower levels of physical activity. Further research is required to determine the long-term effects of excessive body mass on participation in physical activity and whether the walking plantar pressure patterns associated with reduced physical activity are related to foot pain or discomfort.