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I know that the Total Power, SDNN, and Autonomic Balance Diagram are important. What do they represent?

I have heard that it is "not good" if the SDNN and Total Power numbers are low. There are reference ranges in the manual for 24-hour analysis, but are they the same for our 5-minute trials? And generally speaking, is it that any number falling outside the reference range is indicative of problems? Or do low numbers indicate one thing and high numbers another?

I understand the ANS to be the combination of PSNS (parasympathetic nervous system) and SNS (sympathetic nervous system). Does SNS increase heart rate and react to activity and stress/stimulus?

Then does the PSNS decrease heart rate and re-establish balance in the ANS?

Does the PSNS respond to the action taken by the SNS?

I know that in the Balance Diagram, the middle square is more or less where we want our HRV results to come in. And anything outside that means the ANS is out of balance. But I know that's not going to be a sufficient explanation for some clients. How do I explain this?

How do I discuss the 9 possible combinations within the Autonomic Balance Diagram with someone who doesn't understand the PNS and SNS?

Do the results mean different things if you are using different modalities for treatment?

I know that the Total Power, SDNN, and Autonomic Balance Diagram are important. What do they represent?

SDNN is a 24-hour measurement of HRV; Total Power is the Frequency Domain (5-minute) reflection of HRV. The Autonomic Balance Diagram is a reflection of systemic balance as interpreted from HRV.

I have heard that it is "not good" if the SDNN and Total Power numbers are low. There are reference ranges in the manual for 24-hour analysis, but are they the same for our 5-minute trials? And generally speaking, is it that any number falling outside the reference range is indicative of problems? Or do low numbers indicate one thing and high numbers another?

SDNN, being a 24-hour measurement, is good for a reference or baseline only. That is, you would not use 24-hour norms to compare to a 5-minute trial. Numbers outside the 5-minute norms are indicative of ANS imbalances and may represent clinical or subclinical pathology. In general, low Total Power is indicative of a depressed or exhaustive state. High Total Power is a hyper-aroused state. At its extreme this is what we see in conditions such as PTSD or Autism.

I understand the ANS to be the combination of PSNS (parasympathetic nervous system) and SNS (sympathetic nervous system). Does SNS increase heart rate and react to activity and stress/stimulus?

Yes, similar to the accelerator on your car.

Then does the PSNS decrease heart rate and re-establish balance in the ANS?

Yes, similar to using the brakes on your car. PSNS contributes to balance with the SNS in the same manner as you would use the brakes and accelerator together to respond to changing driving conditions and to maintain speed.

Does the PSNS respond to the action taken by the SNS?

As above, it works both ways! Sometimes you can get what appears to be high SNS because the PSNS has withdrawn. Think of it in terms of the brake/gas metaphor - application of either one does not necessarily depend on the other!

I know that in the Balance Diagram, the middle square is more or less where we want our HRV results to come in. And anything outside that means the ANS is out of balance. But I know that's not going to be a sufficient explanation for some clients. How do I explain this?

Remember that the Autonomic Balance Diagram shows systemic balance, not HRV per se. It is derived from HRV through the application of a standardized algorithm (Fast Fourier Transforms). If the results are located along the 45-degree angle from the bottom left corner to the upper right corner of the diagram (sections 1, 5, 9 below), the ANS actually IS balanced! If it is located along this line, but outside the middle square (5), it is a reflection that the system is either over- or under-powered relative to the norms. The description that appears underneath the diagram on the report explains this relationship. The Total Power value is an indicator of your client's "response-ability." That is, their ability to handle systemic challenges (stress, exercise, conflict, pathogens, toxins, etc.)

How do I discuss the 9 possible combinations within the Autonomic Balance Diagram with someone who doesn't understand the PNS and SNS?

Use the gas/brake explanation! When explaining, use the verbiage at the bottom of the Autonomic Balance Report. Do I always want to see my client's results within the middle square (section 5)? In general, moving your client towards balance is best. However, if you are tuning an athlete, you may desire a slight sympathetic dominance. If your purpose is to evoke a healing response, a slight parasympathetic dominance appears to be beneficial.

Do the results mean different things if you are using different modalities for treatment?

The system will show a movement toward or away from balance regardless of the modality.

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