Purpose: Kayak Riders involves repetitive stress movements, and most of the injuries are overuse. Therefore, the aim of this study was to determine the electromyographic activity and the amount of fatigue of selected shoulder muscles during 2 km rowing.

Methods: This is descriptive and quasi-experimental study and the sampling method is purposeful. The statistical sample was eight female national rower who were selected according to the criteria for entering and leaving the research. For test, the 2-kilometer Kayak ergometer was used. Initially, the MVIC test was used to normalize the results. Then, recording the level of muscle activity was done by Surface Electromyography (16 Channel, manufactured by Bayamed Iran). For data analysis, ANOVA with repeated measure design with a significant level of 0.05 and SPSS software version 22 was used.

Results: The results showed that the distance of rowing 2 km had a significant effect on the electromyographic activity of Anterior Deltoid(P≤0.025), Biceps Brachii(P≤0.001), Triceps Brachii(P≤0.041) and Pectoralis major (P≤0.001). There was a significant effect on the fatigue rate of Anterior Deltoid(P≤0.001), Biceps Brachii(P≤0.001), Triceps Brachii(P≤0.049) and Pectoralis major (P≤0.001).

Conclusion: The results of this study show that 2 km rowing has a risk factor for injury in the shoulder girdle structure.The obtained results can be used to design a suitable program to prevent injury and improve of the kayak.