## 4 Discussion  
The main purpose of the study was to examine changes in foot characteristics during quiet standing under the following two conditions: (i) 'no load' vs. (ii) a '3.5 kg load'. The main findings of the study are as follows: (a) when carrying a '3.5 kg load', significant increases in the confidence ellipse area, the center of pressure path length and average velocity, the length of the minor axis, and the deviation in X and Y are observed and (b) significant changes in the relative ground reaction forces beneath the left forefoot and hindfoot regions are shown. \begin{table}
\begin{tabular}{l c c c c c} \hline \hline
**Study Variables** & **Total** & **Men** & **Women** & **ES** & \(p\)**-Value** \\  & **(N = 845)** & **(N = 609)** & **(N = 236)** & **ES** & \(p\)**-Value** \\ \hline Age (years) & 21.3 \(\pm\) 2.1 & 21.1 \(\pm\) 1.9 & 21.4 \(\pm\) 2.4 & 0.02 & 0.987 \\ \hline Height (centimeters) & 176.2 \(\pm\) 12.6 & 181.3 \(\pm\) 10.4 & 171.9 \(\pm\) 11.5 & 0.90 & \textless{}0.001 \\ \hline Weight (kilograms) & 74.2 \(\pm\) 11.8 & 82.6 \(\pm\) 13.4 & 68.7 \(\pm\) 10.9 & 1.04 & \textless{}0.001 \\ \hline Body mass index (kg/m\({}^{2}\)) & 23.9 \(\pm\) 3.1 & 25.2 \(\pm\) 3.6 & 23.2 \(\pm\) 2.9 & 0.56 & \textless{}0.001 \\ \hline \hline \end{tabular}
\end{table} 
Table 1: Basic descriptive statistics of the study participants. \begin{table}
\begin{tabular}{l c c c c} \hline \hline
**Study Variables** & **’No Load’** & **’A 3.5-kg Load’** & **\(\Delta\) (\%)** & **ES** & \(p\)**-Value** \\  & **Median** & **Median** & & & \\  & **(25 th–75 th)** & **(25 th–75 th)** & & & \\ \hline Confidence ellipse area (mm\({}^{2}\)) & 127.0 (76.5–236.0) & 146.0 (85.0–253.0) & 15.0\% & 0.33 & 0.009 \\ \hline Center of pressure path length (mm) & 91.0 (64.5–127.0) & 94.0 (69.0–134.0) & 3.3\% & 0.11 & 0.023 \\ \hline Center of pressure average velocity (mm/s) & 9.0 (6.0–13.0) & 10.0 (7.0–13.0) & 11.1\% & 0.27 & 0.014 \\ \hline Length of minor axis (mm) & 8.5 (6.3–12.0) & 9.2 (6.9–12.5) & 8.2\% & 0.25 & \textless{}0.001 \\ \hline Length of major axis (mm) & 19.4 (14.6–27.2) & 20.3 (15.2–26.9) & 4.6\% & 0.09 & 0.201 \\ \hline Angle btw. Y and major axis (\({}^{\circ}\)) & 77.8 (66.4–84.4) & 77.0 (62.8–84.7) & \(-1.0\%\) & 0.02 & 0.225 \\ \hline Deviation X (mm) & 12.9 (4.0–23.5) & 14.5 (2.0–26.2) & 12.4\% & 0.24 & 0.005 \\ \hline Deviation Y (mm) & \(-3.6\) (\(-9.95\)–3.10) & \(-1.8\) (\(-9.7\)–5.6) & 50.0\% & 0.43 & \textless{}0.001 \\ \hline Relative average force—left forefoot (\%) & 51.0 (47.0–55.0) & 52.0 (48.0–56.0) & 2.0\% & 0.15 & 0.002 \\ \hline Relative average force—left hindfoot (\%) & 49.0 (45.0–53.0) & 48.0 (44.0–52.0) & \(-2.0\%\) & 0.15 & 0.002 \\ \hline Relative average force—left total (\%) & 47.0 (40.0–53.0) & 46.0 (39.0–53.0) & \(-2.1\%\) & 0.10 & 0.345 \\ \hline Relative average force—right forefoot (\%) & 50.0 (46.0–54.0) & 50.0 (45.0–55.0) & 0.0\% & 0.01 & 0.714 \\ \hline Relative average force—right hindfoot (\%) & 50.0 (46.0–54.0) & 50.0 (45.0–55.0) & 0.0\% & 0.01 & 0.578 \\ \hline Relative average force—right total (\%) & 53.0 (47.0–60.0) & 54.0 (47.0–61.0) & 1.9\% & 0.12 & 0.285 \\ \hline \hline \end{tabular}
\end{table} 
Table 2: Basic descriptive statistics and changes in biomechanical static foot parameters under the different loading conditions in police recruits. To the best of the authors' knowledge, this is the first study aiming to investigate the effects of a '3.5 kg load' on spatiotemporal and kinetic foot parameters during quiet standing. Previous evidence has confirmed that heavier loads may impact several foot characteristics during a quiet stance, including increases in the mean postural sway during a double stance, the center of pressure path length, the average velocity and the lengths of the minor and major axes with a decrease in the angle between the Y and major axes [11; 20; 25].