## Materials and Methods
### Study Design and Testing Procedures  
For each subject, we captured measurements of (i) \(\mathrm{k_{RTD-SF}}\), \(\mathrm{T_{MVC}}\), and \(\mathrm{RTD_{PEAK}}\) for EE and VF of the self-reported preferred arm and (ii) shooting performance at two different distances from the basket in two separate visits. On the first measurement day, the subjects performed isometric strength tests for EE and VF (random order) preceded by a 10 min warm-up consisting of 5 min of light running, 4 min of dynamic stretching, and 1 min of activation exercises (10 repetitions of squats, push-ups, and V-ups). The isometric strength tests were performed before their regular training in the laboratory setting. The next day, on the second measurement day, the subjects performed 10 throws at two different distances (random order) from the basket after the standardized warm-up protocol described before. The shooting performance was assessed in the gym basketball gym before their regular training. The flowchart of the study is outlined on the Figure 1.  
\begin{table}
\begin{tabular}{c c c c c c} \hline \hline
**Group** & **N** & **Age (years)** & \begin{tabular}{c} **Body** \\ **Height (cm)** \\ \end{tabular} & \begin{tabular}{c} **Body Mass** \\ **(kg)** \\ \end{tabular} & \
\begin{tabular}{c} **BMI** \\ **BMI** \\ \end{tabular} &
\begin{tabular}{c} **Training History** \\ **(Years)** \\ \end{tabular} \\ \hline Junior & 13 & \(16.5\pm 0.9\) & \(192.7\pm 7.8\) & \(81.5\pm 9.1\) & \(21.9\pm 2.0\) & \(5.5\pm 1.8\) \\ Senior & 10 & \(24.0\pm 4.2\) & \(198\pm 7.9\) & \(95.5\pm 10.9\) & \(24.2\pm 1.6\) & \(14.1\pm 3.8\) \\ Total & 23 & \(19.7\pm 4.8\) & \(195.2\pm 8.2\) & \(87.6\pm 11.9\) & \(22.9\pm 2.1\) & \(9.3\pm 5.2\) \\ \hline \hline \end{tabular}  
N—the number of participants; BMI—Body mass index.  
\end{table}
Table 1: Characteristics of Subjects.  
Figure 1: The flowchart of the measurement protocols. MVC—maximal voluntary isometric contraction.  
Following the warm-up, the subject was positioned in a custom-made dynamometer (S2P, Science to Practice, Itd., Ljubljana, Slovenia) which was used for T\({}_{\text{MVC}}\) and RTD\({}_{\text{PEAK}}\) and k\({}_{\text{RTD-SF}}\) assessment. Participants position during elbow extension or volar flexion T\({}_{\text{MVC}}\), RTD\({}_{\text{PEAK}}\), and k\({}_{\text{RTD-SF}}\) assessment is presented and described in Figure 2. In all cases, the lever arm (i.e., the linear distance from the axis of the joint and the centre of the distal force-detecting support) was measured and considered in the torque calculation. The signals from force transducers during elbow extension (Bending beam load cell 1-Z6 FC3/200 kg, HBM, Darmstadt, Germany) and volar flexion (Tension compression load cell FL25-50 kg, Forsentek, Shenzhen, China) were amplified (Isotel, Logatec, Slovenia) and converted from analogue to digital signal (NI USB-6211, National Instruments, Austin, TX, USA). Signals were sampled at 1000 Hz by a custom-made LabView 2015 software (National Instruments Corp., Augustin, TX, USA). In case of T\({}_{\text{MVC}}\) and RTD\({}_{\text{PEAK}}\), the raw signals were smoothed (moving average filter, 5 ms time-window). In RTD-SF analyses the signals were filtered using a lowpass Butterworth filter with cut-off frequency at 5 Hz, while corresponding RTD of each contraction was calculated as a peak value of derivate of the torque curve [4]. All measurements were processed by a single investigator.