Whole-body electromyostimulation (WB-EMS) training is effective in improving training adaptations and recovery. However, WB-EMS is associated with potential side effects and contraindications that can lead to excessive muscle damage and physiological impairment. This randomized crossover study aimed to analyze the acute effects of WB-EMS on muscle damage, autonomic modulation, and performance fatigability during a single high-intensity cardiovascular training rowing session. › Nineteen healthy and physically active participants, 10 men and 9 women (with a mean 26±4.07 and 25±5.90 years; 75.4±12.43 and 62.0±5.58 kilograms; and 174±7.33 and 164±4.50 centimeters, respectively), randomly performed two rowing sessions, each lasting twenty minutes, with and without WB-EMS (performing a mean of 4069.8±351.7 and 4091.1±498.8 meters (p=0.88); 112.2±28.0 and 116.6±40.2 watts (p=0.70), respectively). Data showed no significant differences between trials for muscle damage (blood creatine kinase levels), lactate blood levels and performance after exercise, except for squat jump’s height which increased in the WB-EMS trial. Likewise, heart rate, blood oxygen saturation and the rate of perceived exertion were similar between trials. › The heart rate variability analysis also showed a similar autonomic response among the trials. WB-EMS resulted to be safe by not negatively affecting the health and performance parameters, while offering a stimulus like regular training in physically active participants, regardless of the delivery of the electrical stimuli. More studies are needed to assess the effectiveness of WB-EMS in improving exercise adaptations during training programs.