Frequently Asked Questions
October 8, 2009
About the Valsalva Wave biometric:
1) What is the Valsalva Wave?
The Valsalva Wave is a blood wave that rises in the arterial system during exhalation and rises in the venous system during inhalation when we are breathing "coherently". If measured at a terminus, we see it as increasing then decreasing blood volume during exhalation and decreasing then increasing blood volume during inhalation.
2) Is the Valsalva Wave the same as Heart Rate Variability?
No, breathing induced Heart Rate Variability is thought to be the autonomic nervous system response to increasing and decreasing blood pressure as a consequence of respiration. Valsalva Wave Pro allows us to observe the action of the blood, to which the autonomic nervous system is responding.
3) What is the advantage of monitoring and training the Valsalva Wave vs. Heart Rate Variability?
Heart rate variability is "variation in heart rate for any reason", including thoughts, emotions, etc. Breathing induced heart rate variability it thought to be a consequence of baroreceptor action due to changes in blood flow and pressure as a consequence of respiration. This variation is the Valsalva Wave. In this regard, heart rate variability is a second order effect.
4) Does one have to employ breathing to generate the Valsalva Wave?
Yes, Valsalva Wave variability is a measure of respiration's contribution to the movement of blood in the body. The mechanism is referred to as the "thoracic pump". A goal is to increase the degree to which breathing moves the blood in the body. This involves breathing slowly, deeply, and with regularity.
5) Does one have to employ the Coherent Breathing method for success in increasing Valsalva Wave variability and coherence?
No, however Coherent Breathing is known to be very effective in facilitating the action of the thoracic pump.
6) What are the health effects of training Valsalva Wave variability?
Valsalva Wave Pro complements a breath retraining program. It helps us train the effectiveness of the thoracic pump rapidly and effectively by allowing us to observe the blood flow effects of respiration. It is thought that when the thoracic pump is working effectively, the rate of blood flow in the body doubles, even though we may be at rest or semi-active.
7) How does the thoracic pump and the Valsalva Wave affect the heart?
The thoracic pump is a larger pumping system which includes the heart. The thoracic pump is powered by the diaphragm a large strong sheath of muscle that governs the volume of the thoracic cavity. It is believed that the thoracic pump plays a vitally important role in moving the blood in the body. When the diaphragm is not "working", the burden of blood flow and pressure fall to the heart and vascular system. When it is working, the heart and vascular system are afforded rest. This rest can be observed in the cycle of the autonomic nervous system. In particular, the thoracic pump plays a vitally important role in venous return, offloading the right heart of this work load.
8) How should we breathe to facilitate proper thoracic pump and Valsalva Wave action?
The diaphragm has a range of movement of ~10cm. The average adult breathes with 1 cm of this range. This effectively defeats the role of the thoracic pump. The goal is to train the diaphragm so we are employing between 40 and 60% of it range. When we learn to employ the diaphragm in this way, with synchrony, Valsalva Wave variability increases.
9) What is the relationship between the Valsalva Wave and heart rate metrics?
Heart rate varies approximate 180 degrees out of phase with the Valsalva Wave. As we exhale, the Valsalva Wave rises in the arterial tree - heart rate slows. When we inhale, the Valsalva Wave falls in the arterial tree - heart rate increases. Again, this is thought to be a function of baroreceptor action as well as cardiac and pulmonary stretch receptors. Generally, as Valsalva Wave variability increases, heart rate variability increases.
10) What is the Valsalva Wave variability training objective?
At present, cultivating Valsalva Wave variability in the range of 2% as measured at the finger tip or ear lobe is believed appropriate. This typically corresponds to heart rate variability in the range of 20-30 beats.