## 3 Results  
The changes in the thicknesses of the fascia and muscle according to absorber usage on B-mode images were compared using image analysis and statistical programs. When comparing the thicknesses of RA, SF, and DF, RA was 12.15 \(\pm\) 2.73 mm and 11.64 \(\pm\) 2.75 mm with No_PU and PU, respectively; however, no significant difference (_p_ = 0.260) was observed. Likewise, the thicknesses for SF were 0.93 \(\pm\) 0.28 mm and 0.89 \(\pm\) 0.24 mm with No_PU and PU, respectively; however, the difference was insignificant (_p_ = 0.318). For DF, the thicknesses were 0.89 \(\pm\) 0.31 mm and 0.78 \(\pm\) 0.21 mm with No_PU and PU, respectively; however, there was no significant difference (_p_ = 0.122) (Table 1 and Figure 2). The inter-rater reliability of the thickness was high (Cronbach's \(\alpha\) = 0.998). For RA, the signal intensities with No_PU and PU were 76.15 \(\pm\) 15.08 and 12.41 \(\pm\) 4.09, respectively, which showed a significant difference (_p_ < 0.001). For SF, the signal intensities with No_PU and PU were 180.02 \(\pm\) 16.53 and 106.26 \(\pm\) 20.33, respectively, which also showed a significant difference (_p_ < 0.001). For DF, the signal intensities with No_PU and PU were 154.90 \(\pm\) 16.87 and 72.72 \(\pm\) 20.39, respectively, which showed a significant \begin{table}
\begin{tabular}{c c c c c c c c c} \hline  & & & **Mean** & **SD** & \
\begin{tabular}{c} **Mean Difference** \\ **(No\_PU-PU)** \\ \end{tabular} & **SE** & **t Statistic** & \(p\) \\ \hline \multirow{4}{*}{
\begin{tabular}{c} **Thickness** \\ **(mm)** \\ \end{tabular} } & \multirow{2}{*}{RA} & No\_PU & 12.15 & 2.73 & \multirow{2}{*}{0.511} & \multirow{2}{*}{0.442} & \multirow{2}{*}{1.16} & \multirow{2}{*}{0.260} \\ \cline{3-3} \cline{5-8}  & & PU & 11.64 & & & & & \\ \cline{3-3} \cline{5-8}  & & No\_PU & 0.93 & 0.28 & \multirow{2}{*}{0.045} & \multirow{2}{*}{1.02} & \multirow{2}{*}{0.318} \\ \cline{3-3} \cline{5-8}  & & PU & 0.89 & 0.24 & \multirow{2}{*}{0.111} & \multirow{2}{*}{0.069} & \multirow{2}{*}{1.60} & \multirow{2}{*}{0.122} \\ \cline{3-3} \cline{5-8}  & & No\_PU & 0.89 & 0.31 & & & & \\ \cline{3-3} \cline{5-8}  & & PU & 0.78 & 0.21 & & & & \\ \hline \end{tabular}
\end{table} 
Table 1: Comparison of the thickness for No_PU and PU. Figure 2: Ultrasound images of a representative subject with PU (**left**) and No_PU (**right**). difference (_p_ < 0.001). For BG, the signal intensities with No_PU and PU were 53.04 \(\pm\) 33.08 and 6.75 \(\pm\) 5.84, respectively, which demonstrated a significant difference (_p_ < 0.001) (Table 2). For RA, the SNRs with No_PU and PU were 13.18 \(\pm\) 5.21 and 5.82 \(\pm\) 3.52, respectively, which demonstrated a significant difference (_p_ < 0.001). For SF, the SNRs with No_PU and PU were 31.37 \(\pm\) 10.73 and 67.07 \(\pm\) 43.87, respectively, which exhibited a significant difference (_p_ < 0.001). For DF, the SNRs with No_PU and PU were 25.64 \(\pm\) 6.67 and 37.54 \(\pm\) 22.23, respectively, which showed a significant difference (_p_ = 0.013) (Table 3 and Figure 3). For SF-RA, the values of the CNR were 16.70 \(\pm\) 6.92 and 50.10 \(\pm\) 26.38 with No_PU and PU, respectively, while for DF-RA, the values of the SNR were 12.30 \(\pm\) 7.97 and 32.00 \(\pm\) 22.53, with No_PU and PU, respectively. Both cases exhibited significant differences (_p_ < 0.001 in each case) (Table 4 and Figure 3).