# Ergonomics Applied to the Development and Evaluation of Insoles for Protective Footwear
## 3 Results and Discussion
### Kinematic Variables  
All variables related to this study were normalized for the gait cycle as well as for the time of the variables obtained by the model. Then, the means and standard deviation for each trial was calculated. In total, 25 gait cycles were obtained for analysis. The kinematic variables analyzed were Ankle_X, Ankle_Y, FETBA_Y, FFHFA_Y, and HXFFA_X, which correspond, respectively, to the ankle angle in the sagittal plane (dorsiflexion/plantar flexion) and in the frontal plane (eversion/inversion), to the tibia angle for joint visualization midtarsal joint (Chopart joint) in the frontal plane, at the angle of the forefoot in relation to the hindfoot, for visualization of the tarsometatarsal joint (Lisfracn joint) in the frontal plane, and the angle of the big toe in relation to the forefoot in the sagittal plane (dorsiflexion only). All kinematic variables were observed between the three environments that participants were asked to execute: (1) barefoot, (2) standard insole, and (3) innovative insole. The insole likely causes stabilization to the foot, but it is necessary to understand whether the magnitude of stabilization is significantly different in the three environments (1, 2, and 3) and whether this stabilization does not compromise functional and individual mobility [31]. Observing the sagittal variation of the ankle, no great difference was observed in the three environments in both feet (Figure 6). The barefoot environment has a greater amplitude in relation to the environments with insole; although it was expected that the insole constrains some of the movement, it did not escape the normality. There is a small variation in terms of the range of motion; effectively, the left foot obtained greater plantar flexion compared to the right foot. On the other hand, the right foot achieved more dorsiflexion when compared to the left foot, yet there was no major discrepancy between the values. Figure 6: Sagittal variation of the left and right ankle in the three environments (barefoot—blue line, standard insole—orange line, and with innovative insole—gray line). Regarding the frontal variation of the ankle, it was found that there were no significant differences between the values in the three environments (barefoot, standard, and innovative); the temporal tracings presented similar behavior. In the left foot, there was a smaller range of motion in the inversion and a greater range in the version when compared to the right foot, which had a greater range in the inversion movement and a smaller range in the even. In addition, it was observed that, in this plane, there were no amplitude constraints in the even and inversion directions due to the use of insoles. Only at the end of the gait cycle on the right foot, in the innovative insole environment, there was a slight reduction in the amplitude of the inversion when compared to other environments. Considering the tendency of the angular variation at the intrinsic midfoot joints, the midtarsal joint presents a very small variation of \(-1\) to \(3\) degrees in the left foot and from \(-4\) to \(0\) degrees in the right foot. In addition, it was observed that the temporal behavior in the three environments were similar (Figure 7). The left foot demonstrated a small range of inversion movement at the beginning of gait and a range of neutral position, while the right foot remained in inversion throughout the cycle. The tarsometatarsal joint also showed a slight variation of \(5\) degrees in the left foot and \(-1\) to \(4\) degrees in the right foot. The behavior was also similar in the three environments. The left foot showed a greater eversion range of motion compared to the right foot, which at the end of the gait cycle reached a small range of inversion and neutral position. Figure 7: Frontal variation of the left and right ankle in the three environments (barefoot—blue line, standard inside—orange line, and with innovative insole—gray line).