## 4 Discussion
### Biomechanical and Qualitative Analysis  
To our knowledge, there is no literature available discussing STG and TG to this date, and this is the first attempt to investigate the velocity and acceleration values of judo athletes' shoulders coming to contact with the tatami. For this reason, this is innovative research in judo research and sports medicine. Both techniques are frequently practiced in judo competitions and, therefore, research on the impact forces and analysis of the velocity and acceleration values are important steps for the assessment of the risk of injury. The biomechanical analysis showed greater peak acceleration and velocity values in TG (0.374 m/s\({}^{2}\), \(-\)0.041 m/s) compared to STG (0.321 m/s\({}^{2}\), \(-\)0.032 m/s). Future studies should explore whether such differences translate to real-world scenarios, such as competition-induced injuries. Defining key terms such as \"impact\" and \"negative velocity\" more explicitly within the context of judo throws would provide greater clarity for readers. Using annotated images or diagrams to highlight kinematic differences between STG and TG techniques could also enhance the visual understanding of these movements. In particular, peak negative velocity was the result to be significantly different (\(p=0.04\)). These data suggests that uke is thrown faster by tori in TG [5; 8; 16; 21]. In the same manner, greater values were observed in knee STG (0.382 m/s\({}^{2}\), 0.035 m/s), compared to standing STG (0.276 m/s\({}^{2}\), 0.321 m/s). However, the difference was insignificant (\(p=0.1\), \(p=0.2\), respectively). On a qualitative level, a notable difference between the throws is that in STG, tori holds [PERSON] from their sleeves, each hand holding the opponent's sleeve, before turning 180 degrees (wide stance) to throw them on the ground. Accordingly, in TG, one of [PERSON]'s hands holds [PERSON] from the gi collar, and the other hand holds [PERSON] from their sleeve, following the same pattern of throwing. Even though the technique execution is similar between the throws, it is differentiated as to where tori is gripping [PERSON]. This essentially means that in TG, [PERSON]'s head momentum is more determined by tori, as the gripping area (collar) is closer to the head and therefore to the body's center of mass (Figure 3). Also, the fact that [PERSON] is gripping [PERSON] from both sleeves in STG gives [PERSON] less control over the landing arm movement and, therefore, the shoulder placement at the point of landing. At the same time, the end-of-sleeve grip in STG gives better control of uke's arm for [PERSON] in order to proceed with a \begin{table}
\begin{tabular}{p{42.7 pt} p{113.8 pt} p{113.8 pt} p{113.8 pt}} \hline  & **Peak Acceleration TG/STG** & **Peak Velocity TG/STG** & **Peak Acceleration Knee STG/Standing STG** \\ \hline \(p\) value Outcome & 0.3 Statistically insignificant & 0.04 Statistically significant & 0.2 Statistically insignificant \\ \hline \end{tabular}
\end{table} 
Table 3: Mean peak acceleration at impact and peak negative velocity in STG with tori kneeling at landing (D–E) recorded to four decimal places. long pull, in contrast with TG, where [PERSON] must execute the throw quickly, since a collar grip indicates throwing uke [22]. This could explain the difference, albeit insignificant, in peak acceleration between the throws. To provide a deeper understanding of the results, future studies should integrate advanced musculoskeletal modeling to analyze shoulder stress mechanisms. For example, factors such as muscle contraction patterns, joint rotation angles, and speed should be examined to explain the uneven stress observed in different throwing techniques. When comparing standing with knee STG throws, uke's shoulder reaches a greater vertical height in standing STG, which gives the shoulder greater potential and ultimately kinetic energy and momentum at impact. The peak velocity would then be greater at the moment of impact, producing greater impact forces [23].