Heart rate variability in athletes with symptoms of non-functional overload

Abstract

The article examines the effect on heart rate variability (HRV) indices in athletes depending on training status, different types of physical exertion, gender and age, presented in both cross-sectional and longitudinal studies. Also included is the predictability of HRV during overtraining, athletic condition, and athletic performance. Heart rate variability (HRV) has long been used as a diagnostic marker of overexertion and overtraining. A large body of evidence shows that in athletes of all ages, regular aerobic training usually results in significant improvements in total and instantaneous HRV. These changes, which are accompanied by a significant decrease in heart rate both at rest and during submaximal exercise, reflect an increase in autonomic efferent activity and a shift in favor of enhanced vagal modulation of heart rate. At present, the available data do not allow us to draw definitive conclusions about the usefulness of traditional HRV indices for evaluating the performance of physical exercises and monitoring the training load. The discrepancies in the results published so far are due to several factors, including insufficient study size and design, and different HRV methods. It also remains to be seen whether traditional HRV indices will be useful for diagnosing overexertion and overtraining.