Effects of urination process on heart rate variability.

Area of Science:

• Physiology
• Autonomic Nervous System Research
• Cardiovascular Monitoring

Background:

• Heart rate variability (HRV) is a key indicator of autonomic nervous system (ANS) activity.
• Urination is a physiological process significantly influenced by the ANS.
• Understanding ANS modulation during urination is crucial for assessing physiological and pathological conditions.

Purpose of the Study:

• To investigate the utility of HRV in assessing ANS function during the peri-urination period.
• To evaluate the psychological impact of sitting positions (chair vs. toilet) on ANS activity before and after urination.

Main Methods:

• Electrocardiogram (ECG) was used to measure HRV in 40 male participants (aged 18-30).
• Sequential HRV measurements were taken in various sitting positions (pre-urination chair, pre-urination toilet, during urination, post-urination toilet, post-urination chair, basal post-urination chair).
• Key HRV indices including SDNN, RMSSD, pNN50, TP, VLF, LF, and HF bands, along with the LF/HF ratio, were analyzed.

Main Results:

• HRV indices demonstrated dynamic changes corresponding to different stages of urination.
• Parasympathetic activity markers (RMSSD, pNN50, HF) increased significantly before urination on the toilet compared to baseline.
• Sympathovagal balance (LF/HF ratio) and heart rate (HR) increased during the urination process itself.

Conclusions:

• HRV analysis effectively captures the physiological shifts in ANS activity during urination.
• The findings indicate distinct patterns of parasympathetic and sympathetic nervous system engagement throughout the peri-urination period.
• HRV is a promising non-invasive tool for studying the complex interplay between the ANS and urinary function.