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What does measurement parameters mean?
Mark avatar
Written by Mark
Updated over 3 months ago

Time-domain parameters:

Heart rate — shows average beats per minute.

Mean RR — average time between each heartbeat in milliseconds.

SDNN (Standard deviation of normal-to-normal RR-intervals) — this number shows whether or not your variability is within the normal range overall. Usually, higher numbers indicate that your body is coping with stress better.

rMSSD (Root mean square successive difference) — reflects parasympathetic activity and shows whether or not the body had a chance to recover.

MxDMn (Difference between maximum and minimum value) — the difference between max and min RR-interval values. The higher it is, the more active your parasympathetic nervous system is, and the better your body recovers.

pNN50 (proportion of NN50) — Proportion of adjacent RR intervals differing by more than 50 ms. Shows how active the parasympathetic system is relative to the sympathetic nervous system. The higher it is, the more relaxed the body is. If the pNN50 is low, you’re either tired or over-stressed.

AMo50 (Mode amplitude) — evaluates the sympathetic activity. The higher it is, the more active the sympathetic system is.

Frequency-domain parameters:

Total Power — reflects the total power of HF, LF, and VLF waves. Shows how much power the body has and how well it’s adapting to stress. Drops when you’re over-stressed or sick.

HF (High frequency) — shows the power of high frequency waves produced by the parasympathetic nervous system. The higher this number is, the more relaxed you are.

LF (Low frequency) — shows the power of low frequency waves produced by the sympathetic nervous system. The higher it is, the more mobilized your body’s systems are.

VLF (Very low frequency)— shows the power of very low frequency waves, which show how the heart is affected by hormones and reflexes. If it’s too high, this means the body is exhausted or sick and the autonomic nervous system isn’t coping with the stress well.

LF/HF — shows which system is working harder: parasympathetic or sympathetic. A value over 2 means the body’s systems are extremely mobilized, and a value of less than 1 means you’re relaxed. A value between 1 & 2 means your systems are balanced.

HF/LF/VLF (Wave balance) — Shows the power of high frequency (HF) waves, low frequency (LF) waves and very low frequency (VLF) waves. Shows which system is currently regulating the heart's activity. The higher HF, the more the body is relaxed. The higher LF, the more the body is mobilized. If VLF is more active - the body is exhausted or sick and doesn't cope with stress.

Important! To get accurate Frequency-domain parameters values, your measurement must be 300 beats long. To change the duration of your measurements, go to Menu, click on Settings, and enable the 300-beat mode.

Blood pressure indices:

Systolic and diastolic blood pressure —  systolic pressure shows blood pressure when your heart beats, and diastolic pressure is your blood pressure when your heart rests between beats. You add these numbers to your measurement yourself, and we calculate the rest of your blood pressure parameters.

Physical state coefficient — assesses the state of the body as a whole and shows how close you are to the norm (depending on your age, blood pressure, height, and weight).

Kerdo’s vegetative index — also shows the balance between stress and recovery, but is calculated based on heart rate and blood pressure. If it’s negative, the body is relaxed. If it’s positive, the body is stressed. If the value is zero, the two are in balance.

Kvas endurance coefficient — reflects the state of your cardiovascular system and shows whether or not your body is ready for physical activity.

Blood circulation efficiency — calculates how much blood the heart pumps per minute and shows if the body’s tissues are getting enough oxygen. The lower it is, the more tired you are.

Robinson’s index — evaluates your cardiovascular system’s reserves and reflects physical health.

Functional changes index — shows how well your body adapts to stress.

Why are some parameters hidden?

Most likely, you didn’t add numbers from your blood pressure reading to the measurement. If you’re not seeing parameters that have nothing to do with blood pressure, let us know in the app’s chat.

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