# Ergonomics Applied to the Development and Evaluation of Insoles for Protective Footwear
## 2 Materials and Methods
### General Procedures  
Kinematic and kinetic variables were obtained simultaneously. Participants were asked to attend a single testing session in the laboratory. Participants received appropriate clothing for the test (for women, tight-fitting spandex fiber shorts and a top and for men, tight spandex fiber shorts).  
After they dressed, the participants' anthropometric data, which was needed for the kinematic and kinetic analysis, was measured. The number of environments which each participant was put through was established according to the classification of the height of the medial longitudinal arch used in this study. Subjects who were classified equally in both feet (symmetrical) performed in an:  
1. Environment consisting of barefoot walking;
2. Environment consisting of walking with the standard insole adjusted to participants' shoe size;
3. Environment based on the innovative insole, according to the participants' foot type classification (normal, flat, and cavus feet).  
\begin{table}
\begin{tabular}{c c c} \hline \hline
**Classification According to Arch Height Index** & **\%** & \\ \hline \multirow{2}{*}{Symmetrical feet} & \multirow{2}{*}{76} & 48\% Both feet normal \\  & & 28\% Both feet flat \\ \multirow{2}{*}{Asymmetrical feet} & \multirow{2}{*}{24} & \\ \hline \hline \end{tabular}
\end{table}
Table 1: Foot type classification.  
Figure 1: Arch height index measures: arch height and truncated foot length, respectively.  
In the case of participants with different foot classification (asymmetry between feet), the data collection was performed in an:  
1. Environment consisting of barefoot walking;
2. Environment consisting of walking with the standard insole adjusted to participants' shoe size;
3. Environment using the normal insole on both feet;
4. Environment consisting of each foot with appropriate insole as to foot type classification (e.g., normal and flat);
5. Environment where both feet wore the corrected insole (e.g., both feet wear a flat insole even if one foot is normal).  
No participant showed extreme difference in flat--cavus relation. These asymmetrical environments were added to understand if there is a need to have a different insole on each foot or if the use of the insole according to the main participant's need is sufficient.  
Each participant received an insole according to their feet size. In order to fix the insole on the participant's foot, a double-sided adhesive tape (Tesa, universal: 50 mm of width) was used on the insole-foot surface. In addition, an elastic adhesive tape (Dreamk kinesio: 97% cotton, 3% elastane, and acrylic adhesive) was used to allow more fixation (Figure 2). The characteristics of the insoles (Figure 3) are shown in Table 2.  
Figure 3: Standard and innovative insoles.  
Figure 2: Insole fixed to the foot.  
Prior to gait data collection, participants were instructed to walk at a comfortable speed across the platform, looking straight ahead, without aiming at the pressure platform. Each participant had 3 min to freely explore the walking corridor for habituation before data collection.  
After participants were adapted to the data collection environment, they were asked to go to the start point and start walking at sign, with a comfortable self-selected speed, until they were asked to stop by the examiner.