Influence of sports training on HRV

Long-term endurance training is the main non-pharmacological factor increasing HRV and individuals trained in this way have a higher level of HRV compared to people with a sedentary lifestyle. This improvement in cardiovascular autonomic control is likely to have training-induced cardioprotective effects. However, a sufficiently large training impulse is needed to achieve positive changes (Carter et al., 2003; Stejskal 2008).

Regular physical activity is accompanied by a subjective feeling of better health, but also by higher values ​​of vagal activity indicators. In longitudinally trained endurance athletes, we find a lower resting heart rate and a faster return of the heart rate to its original size after exercise due to increased parasympathetic activity (Buchheit et al., 2004).

The values ​​of SA HRV parameters can differ significantly from each other in individuals, as well as the response to training load. Finding the optimal ratio between the volume and intensity of training is a key problem of sports training. If the balance between training and recovery is not reached and the athlete's adaptive change is exceeded, his or her overload will occur. With chronic overloading of the athlete's organism, there is a decrease in sports performance, which can be long-term, possibly permanent, so-called overtraining syndrome (Stejskal, 2002, 2008). Disorder of the ANS function is one of the main causes of overtraining. In vagal overtraining, which is typical of the late phase of the syndrome, there are significant signs of reduced sympathetic activity. During overload and in the early phase of overtraining, there is a decrease in ANS performance, which is manifested by a significant decrease in vagal activity and a shift of sympathovagal balance towards the sympathetic nervous system (Stejskal, 2002, 2008, Stejskal & Salinger, 2002).