Cardiac parasympathetic activity may be non-invasively investigated using heart rate
variability (HRV), although HRV is not widely accepted to reflect sympathetic activity …

This article evaluates the suitability of low frequency (LF) heart rate variability (HRV) as an
index of sympathetic cardiac control and the LF/high frequency (HF) ratio as an index of …

Components of heart rate variability have attracted considerable attention in psychology and
medicine and have become important dependent measures in psychophysiology and …

This review examines the influence on heart rate variability (HRV) indices in athletes from
training status, different types of exercise training, sex and ageing, presented from both …

Given the importance of the autonomic nervous system to cardiovascular health, it is not
surprising that there is and has been great interest in measurements of human sympathetic …

Long-term endurance training significantly influences how the autonomic nervous system
controls heart function. Endurance training increases parasympathetic activity and …

The rhythmic components of heart rate variability (HRV) can be separated and quantitatively
assessed by means of power spectral analysis. The powers of high frequency (HF) and low …

Power spectral analysis (PSA) of heart rate variability (HRV) offers reliable assessment of
cardiovascular autonomic responses, providing a 'window'onto the interaction of peripheral …

Accurate estimation of heart rates from photoplethysmogram (PPG) signals during intense
physical activity is a very challenging problem. This is because strenuous and high intensity …

There are two major approaches to heart rate variability analysis: time domain analysis and
frequency domain (power spectrum) analysis. This review considers the normal power …