Comparison of ground reaction forces between obese and control young adults during quiet standing on a baropodometric platform

Objective. To determine whether centre of pressure location, plantar surface areas, or plantar pressures differ between obese and control young adults during quiet standing. Design. Cross-sectional study in university setting. Background. Given the characteristic distribution of body fat in obesity, it is possible that obesity may systematically alter centre of pressure location, plantar ground contact areas and pressure distributions in males and females. Methods. Thirty-eight obese subjects (23 women and 15 men) and 34 healthy controls (18 women and 16 men) with a mean age of 23 years were studied. Subjects were asked to stand bipedally on a baropodometric platform while centre of pressure location, plantar ground contact surface areas and pressures were measured over a 5 s interval. Group differences were examined by analyses of variance and Fisher's PLSD test. Results. No significant group differences were found in centre of pressure location by weight or gender. Obesity was associated in both sexes with significantly larger plantar contact areas (+12.2%, P < 0.0001 for women and +9.9%, P < 0.005 for men) and pressures (mean load: +52.6% for women and +44.7% for men, P < 0.0001 in both of sexes; peak pressure: +45.5% for women and +40.5% for men, P < 0.0001 in both of sexes). There were significant gender differences in plantar contact areas (P < 0.0001), while were no significant differences in mean and peak pressures. Conclusions. Although centre of pressure location was unaffected by obesity, these young obese individuals showed significantly increased plantar contact areas and pressures.