Aim: The aim of the study is to investigate the correlation between the times for overcoming the distance of 2000 m achieved in control tests on the water and the anaerobic threshold determined by the X-method in laboratory conditions. Material and Methods: Includes collection and analysis of the times achieved in overcoming the distance of 2000 m and the anaerobic threshold determined by the X-method, related to the individual ergometric power and heart rate for each participant. Five elite rowers from the National Team of Bulgaria, men, for the period from 2018 to 2021 were examined. To determine the anaerobic threshold by the X-method, we used the data from minute pulmonary ventilation and heart rate recorded every 20 s during the maximum spiroergometric test with increasing intensity. The test was performed on a Concept II rowing machine and equipment measuring pulmonary ventilation and heart rate. Results: The Pearson coefficient r = .457 ( = .05) shows a moderate correlation between the times for overcoming the distance of 2000 m, and the heart rate recorded at the anaerobic threshold determined by the X-method. Conclusion: The X-method for determining the anaerobic threshold is an relevant method in the control of the training process and has prognostic value in determining the functional status of rowers. An advantage is the significantly lower cost of the used diagnostic equipment compared to the cost of a conventional gas analyzer.