Background: Excessive body weight seems to be a risk factor for foot loading. We sought to investigate the effect of different body mass index (BMI) levels on plantar pressure distribution during walking.
Methods: In total, 163 women aged 45 to 65 years (mean ± SD: age, 57.4 ± 5.3 years; BMI, 27.0 ± 5.3) participated in the study. The women were divided, on the basis of BMI, into a normal-weight, overweight, or obese group. The study used the four following plantar pressure parameters (PPPs): contact percentage, absolute pressure impulse, relative pressure impulse, and absolute peak pressure, which were recorded in ten foot regions using a pressure measurement system.
Results: The normal-weight group, compared with the overweight and obese groups, had significantly lower absolute PPP values. In the hallux, second through fifth metatarsals, midfoot, and heel regions, we observed significant between-group differences in the two absolute PPPs (peak pressure and pressure impulse) (P < .001). Between-group differences in the relative PPPs were found in the fourth metatarsal, midfoot, and medial heel (relative impulse) and in the second metatarsal (contact percentage) (P < .001).
Conclusions: Higher BMI values correspond to a higher load on the foot during walking in women. The relative foot load in obese women is characterized by a pressure increase in the lateral forefoot and midfoot and by a pressure decrease in the medial heel.