## 2 Materials and Methods
### Statistical Analysis  
All data were checked for normality using the Shapiro-Wilk test. As a preliminary evaluation, a two-way repeated-measures ANOVA (TRIAL \(\times\) METHOD) was performed to test differences in the mean concentric time (expressed as % of the total time), mean vertical displacement (initial and final positions expressed as % of box height and participants' stature, respectively), and mean force values (expressed as % of body weight) between the two trials. Since there was no main significant effect of TRIAL on the outcomes, the values of the two trials were averaged for each participant. A two-way, repeated measures ANOVA (SEX \(\times\) METHOD) was performed to test differences in the time, position, and force between the assumed [PERSON]'s and the laboratory-measured values. \begin{table}
\begin{tabular}{c c c c c c c c c c c c c} \hline \hline  & \multicolumn{4}{c}{**Males (\(\alpha\) = 30)**} & \multicolumn{4}{c}{**Females (\(\alpha\) = 29)**} & \multicolumn{4}{c}{**Total (\(\alpha\) = 60)**} & \multicolumn{4}{c}{**Mine Effect**} \\ \hline \multirow{4}{*}{Duration} & \multicolumn{2}{c}{**Estimated**} & \multicolumn{1}{c}{**Measured**} & \(p\) & **Estimated** & **Measured** & \(p\) & **Estimated** & **Measured** & \(p\) & **Method** & **Sex** & **Interaction** \\ \cline{3-13}  & \multicolumn{2}{c}{Constrict phase} & \multicolumn{1}{c}{(\(10.0\pm 0.0\))} & \(8.3\pm 1.0\) & \(<\)0.001 & \(10.0\pm 0.0\) & \(8.1\pm 1.0\) & \(<\)0.001 & \(10.0\pm 0.0\) & \(8.2\pm 1.0\) & \(<\)0.001 & \(<\)0.001 & 0.55 & 0.55 \\ \cline{3-13}  & \multicolumn{2}{c}{Constrict time (s)} & \(1.0\pm 0.2\) & \(0.8\pm 0.1\) & \(<\)0.001 & \(1.0\pm 0.3\) & \(0.8\pm 0.1\) & \(<\)0.001 & \(1.0\pm 0.3\) & \(0.8\pm 0.1\) & \(<\)0.001 & \(<\)0.001 & 0.962 & 0.302 \\ \hline \multirow{4}{*}{Position} & \multicolumn{2}{c}{(\%: chair height)} & \multicolumn{1}{c}{\(100.0\pm 0.1\)} & \(118.5\pm 4.3\) & \(<\)0.001 & \(100.0\pm 0.0\) & \(118.9\pm 3.2\) & \(<\)0.001 & \(100.0\pm 0.0\) & \(118.7\pm 3.8\) & \(<\)0.001 & \(<\)0.001 & 0.801 & 0.801 \\ \cline{3-13}  & \multicolumn{2}{c}{Stop} & \multicolumn{1}{c}{(\%: stature)} & \multicolumn{1}{c}{\(50.0\pm 0.0\)} & \(53.9\pm 0.0\) & \(<\)0.001 & \(50.0\pm 0.0\) & \(54.5\pm 0.0\) & \(<\)0.001 & \(50.0\pm 0.0\) & \(54.2\pm 2.0\) & \(<\)0.001 & \(<\)0.001 & 0.148 & 0.148 \\ \cline{3-13}  & \multicolumn{2}{c}{Dipacement (m)} & \multicolumn{1}{c}{\(0.4\pm 0.03\)} & \(0.3\pm 0.1\) & \(<\)0.001 & \(0.3\pm 0.0\) & \(0.3\pm 0.0\) & \(<\)0.001 & \(0.3\pm 0.0\) & \(0.3\pm 0.0\) & \(<\)0.001 & \(<\)0.001 & \(<\)0.001 & 0.422 \\ \cline{3-13}  & \multicolumn{2}{c}{Mean concentric} & \multicolumn{2}{c}{\(0.4\pm 0.1\)} & \multicolumn{1}{c}{\(0.5\pm 0.1\)} & \(<\)0.001 & \(0.3\pm 0.1\) & \(0.4\pm 0.1\) & \(<\)0.001 & \(0.3\pm 0.1\) & \(0.4\pm 0.1\) & \(<\)0.001 & \(<\)0.001 & \(<\)0.001 & 0.765 \\ \cline{3-13}  & \multicolumn{2}{c}{\%: BW} & \multicolumn{1}{c}{\(90.0\pm 0.0\)} & \(69.2\pm 5.3\) & \(<\)0.001 & \(90.0\pm 0.0\) & \(67.7\pm 8.26\) & \(<\)0.001 & \(90.0\pm 0.0\) & \(66.5\pm 6.8\) & \(<\)0.001 & \(<\)0.001 & 0.402 & 0.402 \\ \cline{3-13}  & \multicolumn{2}{c}{Newton} & \multicolumn{2}{c}{\(710.2\pm 126.6\)} & \multicolumn{1}{c}{\(543.7\pm 92.0\)} & \(<\)0.001 & \(583.7\pm 102.9\) & \(424.2\pm 120.7\) & \(<\)0.001 & \(580.7\pm 102.9\) & \(490.1\pm 99.9\) & \(<\)0.001 & \(<\)0.001 & \(<\)0.001 & 0.002 \\ \hline \hline \end{tabular}
\end{table} 
Table 3: Elements of the [PERSON]’s calculation of s-to-stand (STS) mean power. A two-way, repeated measures ANOVA (SEX \(\times\) METHOD) was used to test differences between field-estimates and laboratory measures of muscle power. Moreover, the absolute level of agreement between estimated and measured power was investigated using Pearson's correlation coefficient (r), Bland-Altman analysis. The correlation coefficient was interpreted according to the values of the r: trivial (<0.1); small (0.10-0.29); moderate (0.30-0.49); large (0.50-0.69); very large (0.70-0.89); extremely large (0.90-1.00) [19].