Background: Technological advancements have made gaming a central part of adolescents' lives, with PUBG being a popular yet addictive game linked to prolonged screen use and poor postures. This can lead to musculoskeletal issues like up-per trapezius fatigue and reduced hand functionality. While the psychological effects of gaming addiction are well-document-ed, its physical impacts on muscle activity and grip strength remain under explored, high lighting the need for this study. Aim of Study: To investigate the effect of Player Unknown's Battle Grounds (PUBG) game addiction on upper trapezius muscle activity, hand grip strength and pinch grip strength in adolescents. Material and Methods: This cross-sectional study inves-tigated the effect of PUBG game addiction on upper trapezius muscle activity, hand grip strength, and pinch grip strength in adolescents. The study was conducted in international schools and clubs in 10th of Ramadan City, Cairo, Egypt, and included sixty adolescents aged 10–19 years. Participants were divid-ed into two equal groups: Group (A), the non-addicted group, and group (B), the addicted group. The main outcome meas-ures included upper trapezius (UT) root mean square (RMS), electromyography (EMG) turns, hand grip strength, and pinch grip strength. Additionally, data from the addicted group were collected regarding UT RMS and EMG turns before starting PUBG, after 15 minutes of playing, and after 30 minutes of playing. Results: Statistically significant differences were observed between groups in All measured outcomes (p<0.001). From baseline to 15 minutes of gameplay, significant reductions were recorded in Upper Trapezius Root mean square (MD = –7.87, 95% CI: –9.16 to –6.57, p<0.001) and Electromyography turns (MD = –1.43, 95% CI: –1.81 to –1.05, p<0.001). Similarly, from baseline to 30 minutes of gameplay, Upper trapezius Root mean square (MD = –16.6, 95% CI: –18.68 to –14.52, p<0.001) and Electromyography turns (MD = –3.33, 95% CI: –3.8 to –2.87, p<0.001) showed further significant reductions. Conclusion: PUBG game addiction significantly affects physical health in adolescents. Specifically, it leads to increased activity in the upper trapezius muscle and decreased hand grip and pinch grip strength when comparing addicted adolescents to non-addicted adolescents one. These findings suggest that excessive gaming could negatively impact muscle activity and physical function in this age group. The sustained muscle activ-ity could result in muscle imbalance and discomfort over time. Additionally, the decrease in hand grip and pinch grip strength indicates impaired physical function and reduced muscle en-durance.