During VNS analysis, the fluctuations in heart rate at rest are analyzed as they reflect the activation state of the autonomic nervous system. A total of 520 heartbeats are measured, specifically the time intervals between each heartbeat (RR intervals). If there is variability (different time intervals) observed, it indicates that the body can effectively adapt to internal and external stimuli. However, if no variability is observed in the heart rate variability (HRV) analysis, it means that the body is unable to adequately or not at all adjust to internal and external stimuli. In such a situation, the body is in a sympathicotonic state, with the parasympathetic system partially rigid.
Greater variability in heart rhythm measurement indicates a stronger activation of the parasympathetic system (recovery/regeneration).
Less variability indicates a stronger activation of the sympathetic system (fight/flight).
The HRV analysis, performed at rest and in a seated position, should demonstrate a more active parasympathetic system than the sympathetic system, as this measurement situation does not reflect a fight or flight response.