Heart Rate Variability During Physical Exercise

Heart rate variability (HRV) is the present oscillation of the heart rate. The interest in HRV as a parameter of the parasympathetic and sympathetic influence of the autonomic nervous system on the heart has increased in the last few decades (Kaikkonen et al., 2007). It is known that its influence changes under different conditions such as rest, exercise or mental stress and different body postures (supine, sitting, standing). Results how its influence changes during exercise have been inconsistent (Boettger, 2010, Tulppo et al., 1996). HRV parameters are used as indicators for fatigue or overtraining (Aubert et al., 2003).