Changes in footprint with resistance exercise.

We aimed to describe the changes in footprint characteristics after 2 types of resistance training sessions performed at different intensities. 18 young subjects (8 men and 10 women) volunteered for the study. All of them performed 2 different resistance training sessions, one with light loads (LS) and the other with heavy loads (HS). Their footprint was recorded and analysed before and after exercise. Lengths, widths, and areas of the footprint (rearfoot, midfoot, and forefoot) were measured. Almost all the variables significantly increased after both sessions. The greatest changes were found in the midfoot (area, LS: 10.4%; HS: 8.1%, P<0.0005; width, LS: 7.5%, P=0.002, and HS: 8%, P<0.0005). However, there were no significant differences between post-exercise data from both sessions. The variable that showed the smallest changes was the foot length (LS: 0.3%, P=0.023; HS: -0.4%, P=0.549). A resistance training session led to increases in most of the dimensions of the footprint, regardless of the magnitude of the loads handled. The greatest changes were found in the midfoot, indicating that the foot was flatter after exercise, and the foot changed more in width than in length. © Georg Thieme Verlag KG Stuttgart · New York.