# Ergonomics Applied to the Development and Evaluation of Insoles for Protective Footwear
## 3 Results and Discussion
### Plantar Pressure Variables

Table 3: \(t\)-test: paired two samples for means total plantar pressure (N/cm\({}^{2}\)). INV in any of the gait rockers. H\({}_{1}\), \(\mu_{\text{std}}\) > \(\mu_{\text{inv}}\) means that there is a significant difference between the insoles in some gait rockers and that one average is better than the other; that is, the insole with the lowest average is considered the best. Therefore, according to the results obtained, it was verified that there are significant differences between the insoles and that the INV showed a reduction in the maximum plantar pressure in the rockers represented by the forefoot (32.99 N/cm\({}^{2}\)) and the hindfoot (25.67 N/cm\({}^{2}\)) in both feet (one-tailed _p_-value < 0.05) when comparing the average pressures of the STD in these rockers (34.31 N/cm\({}^{2}\) and 26.97 N/cm\({}^{2}\), respectively), as seen in Table 4. According to [PERSON] et al. (2017), the place most affected by pain and discomfort from footwear is the forefoot, which demonstrates a significant result with the use of the INV. In the midfoot in the right feet, there was a significant increase in plantar pressure, which was expected due to the improvement in the pressure distribution through the reduction in the local pressure peaks and the extension of the contact area caused by the INV ([PERSON] et al., 2017). For participants who presented asymmetry, the same hypothesis test was performed: H\({}_{0}\), \(\mu_{\text{std}}\) = \(\mu_{\text{inv}}\) and H\({}_{1}\), \(\mu_{\text{std}}\) > \(\mu_{\text{inv}}\). When comparing the STD and the INV, it was found that there are no significant differences between the insoles of these participants in any of the gait rockers, with the exception of the rocker represented by the midfoot (one-tailed _p_-value < 0.05), which showed a significant difference between the insoles, and the STD had a better average (17.17 N/cm\({}^{2}\)) when compared to the innovative insole (18.13 N/cm\({}^{2}\)). Although they do not show significant differences according to the _t_-test, it is possible to observe through the average values that the INV obtained better results in the forefoot and hindfoot (Table 5). Then, when comparing the INV with the insoles used in environment four called INV4, which corresponds to the environment composed of each foot with an adequate insole regarding the classification of the type of foot, the results achieved were significant only in the right hindfoot, which showed a reduction in the mean plantar pressure from the INV (26.85 N/cm\({}^{2}\)) to the INV4 (25.75 N/cm\({}^{2}\)) with a one-tailed _p_-value = 0.02. The other \begin{table}
\begin{tabular}{c c c c c c} \hline \hline  & **Mean STD** & **s.d.** & **Mean INV** & **s.d.** & **One-Tailed _p_-Value** \\ \hline Left foot & Forefoot & 34.31 & 6.8 & 32.99 & 6.5 & 0.01 \\  & Midfoot & 17.34 & 5.6 & 17.79 & 5.6 & 0.13 \\  & Hindfoot & 26.97 & 4.8 & 25.67 & 4.3 & 0.00 \\ Right foot & Forefoot & 35.30 & 7.2 & 33.20 & 5.7 & 0.03 \\  & Midfoot & 16.88 & 4.7 & 18.52 & 5.2 & 0.00 \\  & Hindfoot & 27.31 & 4.7 & 26.12 & 3.7 & 0.02 \\ \hline \hline \end{tabular} Note: STD—standard insole; INV—innovative insole; s.d.—standard deviation.  
\end{table} 
Table 4: _t_-test: paired two samples for means maximum plantar pressure (N/cm\({}^{2}\)). \begin{table}
\begin{tabular}{c c c c c c} \hline \hline  & **Mean STD** & **s.d.** & **Mean INV** & **s.d.** & **One-Tailed _p_-Value** \\ \hline Left foot & Forefoot & 33.86 & 7.1 & 32.06 & 5.0 & 0.08 \\  & Midfoot & 18.47 & 5.6 & 18.5 & 5.3 & 0.47 \\  & Hindfoot & 25.94 & 4.2 & 25.51 & 5.1 & 0.33 \\ Right foot & Forefoot & 36.51 & 5.6 & 35.31 & 5.5 & 0.31 \\  & Midfoot & 17.17 & 2.5 & 18.13 & 3.3 & 0.03 \\  & Hindfoot & 28.1 & 4.7 & 26.85 & 3.6 & 0.08 \\ \hline \hline \end{tabular} Note: STD—standard insole; INV—innovative insole; s.d.—standard deviation.  
\end{table} 
Table 5: _t_-test: paired two samples for means maximum plantar pressure of asymmetric participants (N/cm\({}^{2}\)).