EMG activity of abdominal muscles during isometric V-sit in athletes from diverse sports

Abstract Background This study aimed to observe the electromyographic (EMG) activities of rectus abdominis (RA) during the isometric V-sit and symmetry of the bilateral RA. Methods Sixteen college students were recruited, with 9 weightlifters and 7 soft tennis players. By using Noraxon EMG system, the EMG signals of the left (RA-L) and right RA (RA-R) were investigated during isometric V-sit at heights of 10 cm, 20 cm, and 30 cm from the ground. Results EMG signals of RA-L in soft tennis players were 13.6% higher than those in weightlifters for three phases of V-sit (p < .05). During the 10 cm phase, EMG activities of both RA-L and RA-R were significantly higher in soft tennis players compared to weightlifters (p < .05). Large negative correlations were found between phase and EMG amplitude in weightlifters (RA-L: r = − .552; RA-R: r = − .665, p < .05), while positive correlations existed in soft tennis players (RA-L: r = .373; RA-R: r = .631, p < .05). Conclusion The study indicated differences in the impact of isometric V-sit heights on RA activation. The correlation trends between RA signals and phases reflected variations in RA strength and control among different exercise types.