## 3 Results  
The participants' characteristics are presented in Table 1.  
No significant difference was noted in age, weight, heart rate and blood pressure, and blood lipid and catecholamine levels among the CON, URT, and LRT groups prior to the intervention (\(P\geq\) 0.16; Table 1). No significant difference was observed in body composition parameters, including weight, body mass index, percent body fat, muscle mass, and segmental (trunk, arm, and leg) LBM, among the three groups at baseline (\(P\geq\) 0.21; Table 1). As expected, the abovementioned body composition factors did not change in the CON group after maintaining a nonexercise lifestyle during the intervention. The URT group had a significant improvement in muscle mass and arm LBM (\(P\leq\) 0.01); however, the LRT group showed no improvement in muscle mass and leg LBM after the established intervention (\(P\geq\) 0.12; Table 1). An increased trunk LBM was observed in the URT and LRT groups following the training (\(P\leq\) 0.02; Table 1). As a result of resistance training, the maximal strength of every exercise in both URT and LRT groups significantly improved between 14.0 and 24.3% (\(P\leq\) 0.006; Table 2). \begin{table}
\begin{tabular}{c c c c c c c} \hline \hline \multirow{2}{*}{**Variables**} & \multicolumn{2}{c}{**CON (\(\boldsymbol{r}\) = 8)**} & \multicolumn{2}{c}{**URT (\(\boldsymbol{n}\) = 8)**} & \multicolumn{2}{c}{**LRT (\(\boldsymbol{n}\) = 8)**} \\  & **Pre** & **Post** & **Pre** & **Post** & **Pre** & **Post** \\ \hline Age, years & 21 \(\pm\) 1 & - & 20 \(\pm\) 1 & - & 20 \(\pm\) 1 & - \\ Height, cm & 164.4 \(\pm\) 1.2 & - & 172.8 \(\pm\) 4.7 & - & 170.2 \(\pm\) 2.0 & - \\ Weight, kg & 60.0 \(\pm\) 3.3 & 59.0 \(\pm\) 3.5 & 65.0 \(\pm\) 4.9 & 67.6 \(\pm\) 5.7 & 65.1 \(\pm\) 3.6 & 63.4 \(\pm\) 4.0 \\ BMI, kg/m\({}^{2}\) & 21.8 \(\pm\) 1.1 & 21.8 \(\pm\) 1.2 & 21.5 \(\pm\) 0.6 & 21.9 \(\pm\) 0.7 & 22.4 \(\pm\) 0.9 & 22.7 \(\pm\) 1.0 \\ Body fat \% & 23.1 \(\pm\) 2.5 & 23.9 \(\pm\) 2.3 & 18.5 \(\pm\) 2.4 & 17.4 \(\pm\) 2.5 & 24.3 \(\pm\) 2.2 & 25.8 \(\pm\) 2.4 \\ Muscle mass, kg & 25.0 \(\pm\) 1.3 & 24.8 \(\pm\) 1.2 & 30.2 \(\pm\) 3.4 & 31.0 \(\pm\) 3.4 \({}^{*}\) & 27.6 \(\pm\) 2.2 & 28.1 \(\pm\) 2.1 \\ Trunk LBM, kg & 20.0 \(\pm\) 1.0 & 19.7 \(\pm\) 0.9 & 22.4 \(\pm\) 2.0 & 23.2 \(\pm\) 2.2 \({}^{*}\) & 20.9 \(\pm\) 1.4 & 21.3 \(\pm\) 1.4 \({}^{*}\) \\ Arm LBM, kg & 2.3 \(\pm\) 0.2 & 2.2 \(\pm\) 0.2 & 2.6 \(\pm\) 0.3 & 2.8 \(\pm\) 0.4 \({}^{*}\) & 2.4 \(\pm\) 0.2 & 2.4 \(\pm\) 0.2 \({}^{*}\) \\ Leg LBM, kg & 7.0 \(\pm\) 0.3 & 7.1 \(\pm\) 0.3 & 8.7 \(\pm\) 1.1 & 8.8 \(\pm\) 1.0 & 8.0 \(\pm\) 0.6 & 8.1 \(\pm\) 0.6 \\ rHR, beat/min & 59 \(\pm\) 3 & 58 \(\pm\) 2 & 58 \(\pm\) 3 & 52 \(\pm\) 2 \({}^{*}\) & 57 \(\pm\) 3 & 53 \(\pm\) 3 \\ SBP, mmHg & 110 \(\pm\) 2 & 111 \(\pm\) 4 & 115 \(\pm\) 4 & 114 \(\pm\) 4 & 113 \(\pm\) 3 & 109 \(\pm\) 4 \\ DBP, mmHg & 64 \(\pm\) 2 & 64 \(\pm\) 2 & 64 \(\pm\) 2 & 61 \(\pm\) 3 & 63 \(\pm\) 1 & 63 \(\pm\) 3 \\ Triglyc, mg/dL & 64 \(\pm\) 6 & 74 \(\pm\) 13 & 66 \(\pm\) 8 & 67 \(\pm\) 7 & 71 \(\pm\) 11 & 72 \(\pm\) 12 \\ Epi, pg/mL & 43 \(\pm\) 2 & 35 \(\pm\) 3 & 41 \(\pm\) 2 & 32 \(\pm\) 3 & 52 \(\pm\) 7 & 34 \(\pm\) 3 \\ Norepi, pg/mL & 325 \(\pm\) 33 & 128 \(\pm\) 14 \({}^{*}\) & 413 \(\pm\) 36 & 140 \(\pm\) 15 \({}^{*}\) & 372 \(\pm\) 25 & 118 \(\pm\) 19 \({}^{*}\) \\ \hline \hline \end{tabular} Data are mean \(\pm\) SE. Abbreviations: CON, nontraining control group; URT, upper-limb resistance training group; LRT, lower-limb resistance training group; BMI, body mass index; LBM, lean body mass; rHR, resting heart rate; SBP, systolic blood pressure; DBP, diastolic blood pressure; Triglyc, triglycerides; Epi, epinephrine; Norepi, norepinephrine. There was no significant group difference at pre-intervention.  
\({}^{*}\)\(P\leq\) 0.05 vs. pre-intervention.  
\end{table} 
Table 1: Participant characteristics pre- and post-intervention. In response to the 8-week intervention, AIx was significantly reduced in the URT group (\(P\) = 0.01; Figure 1A), but no change was noted in the LRT and CON groups.