Physiological effects acting on HRV

Many factors in our lives (eg body position, gender, age, stress, exercise and more) affect heart rate and its variability. To avoid skewing the interpretation of the results of short-term HRV records, these factors must be taken into account.

When changing the position of the body from lying to standing, the sympathetic excitation occurs and at the same time the vagotonia is reduced, therefore this maneuver is used as a sympathetic stress stimulus. In older age and in some pathological conditions, the response of ANS to changes in body position decreases (Javorka, 2008).

With psychological stress, the heart rate increases and its variability decreases, the value of the HF component decreases and at the same time the values ​​of the VLF and LF components increase. With long-term stress on ANS, sympathetic activity increases. Changes in the activity of ANS are also likely to contribute to the development of atherosclerosis or hypertension. Evaluating changes in HRV in response to mental stress can help us predict the level of cardiovascular risk (Tonhajzer, 2008).

Age is one of the basic physiological characteristics affecting the resulting values ​​of HRV components. Thus, age specifically affects most of the monitored parameters of SA HRV. When monitoring differences in the regulation of the cardiovascular system associated with age, it is difficult to distinguish the effects of aging from the effects of disease or fitness. In older age, the functions of the vegetative system deteriorate in healthy individuals and its cooperation with the heart and blood vessels is disrupted (Javorka, 2008).