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.
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.
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).
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.