## 4 Discussion  
This study aimed to verify the immediate effects of dynamic cupping on shoulder AROM of senior male handball players. In this investigation, compared to the control group, dynamic cupping demonstrated a statistically significant increase in senior male handball athlete shoulder AROM in all movements. According to the systematic review of [PERSON] et al. (2018) [8], the relationship between cupping and range of motion remains unclear, although they report that increased range of motion seems to occur due to muscle relaxation induced by cupping. Despite not being in the same anatomical region, the results observed in this study are in line with the investigation by [PERSON] et al. (2014) [30]. The authors found that static cupping  
Figure 3: Descriptive plots of control group AROM (\({}^{\circ}\)) before (M0) and after intervention (M1): Panel (**A**)—Flexion; (**B**)—Extension; (**C**)—Internal rotation; (**D**)—External rotation; (**E**)—Adduction; (**F**)—Abduction; (**G**)—Horizontal adduction; (**H**)—Horizontal abduction. Figure 2: Descriptive plots of intervention group AROM (\({}^{\circ}\)) before (M0) and after intervention (M1): Panel (**A**)—Flexion; (**B**)—Extension; (**C**)—Internal rotation; (**D**)—External rotation; (**E**)—Adduction; (**F**)—Abduction; (**G**)—Horizontal adduction; (**H**)—Horizontal abduction. significantly improved the flexion AROM of the lumbar spine and straight leg raise in the left leg. According to the authors, the results of the intervention are due to a decrease in muscle tension, because cupping promotes the improvement of blood circulation, which maximizes metabolic exchanges. In their study, it was demonstrated that the increased range of motion in these patients was similar to the effects of thermotherapy on muscle tissue, with acute vasodilitation that prompted increased blood flow, facilitating cell and muscle regeneration and increased AROM. In another study, [PERSON] (2015) [PERSON] (2015) assessed shoulder AROM using goniometry in healthy subjects. The movements assessed were flexion, abduction, internal rotation, and external rotation. To assess the movements, the author used a different methodology (evaluation in the supine position). Comparing to the control group, cupping significantly improved the internal and external rotation movements. However, the participants in this study were not athletes; the author only assessed internal and external rotation of the shoulder, and the intervention was performed with static cupping for 5 min, where four plastic cupping cups (5 cm in diameter) were applied to the medial border of the scapula and in the inferior and superior angles of the scapula. A last plastic cupping cup (with a 7.6 cm in diameter) was placed under the scapular spine, in the infraspinatus muscle. In the study of [PERSON] (2016) [PERSON] (2016), static cupping with scarification was compared to a control group on low back pain of soccer players. The outcome measures were the Sorensen's Test and the AROM of the lumbar spine assessed through goniometry. The authors found that compared to a control group, cupping caused significantly improvements in the Sorensen's Test, as well as the flexion and extension active movements of the lumbar spine. In the intragroup analysis, cupping significantly improved all outcome measures, while in the control group, no differences were found. The observed improvements in shoulder AROM following dynamic cupping therapy are likely due to several physiological mechanisms. First, dynamic cupping enhances local blood flow by creating a vacuum effect, which promotes vasodilation and improves tissue perfusion. This increase in blood circulation delivers more oxygen and nutrients to the affected area, aiding in muscle recovery and reducing stiffness. Second, the technique facilitates myofascal release by loosening adhesions and improving the viscoelastic properties of the fascia and muscle tissue. This reduces mechanical restrictions and enhances mobility.