eSense Skin Response
Heart Rate Variability and Biofeedback Training
In order to reduce stress and its symptoms, biofeedback training can be performed seeking to increase heart rate variability.
Biofeedback training is quite applicable to heart rate variability In stress medicine and psychophysiology, HRV biofeedback is used for depression, heart disease, asthma, anxiety disorders and insomnia. HRV biofeedback is also widely used in coaching and competitive sports. Improving HRV and the connection between breathing and the heart can help relieve tension, cope with stress and anxiety, and contribute to a more relaxed response in everyday life. If you suffer from a serious disorder or medical condition, always consult a professional physician or therapist, and do not attempt to treat yourself. The eSense Pulse is not a medical device and may only be used to reduce stress.
The eSense Pulse is a very precise device. It can record heartbeats and display them, for example, as a measurement curve. Take a look at the following example of a measurement at rest and with even, slow breathing:
As you can see in the example above, the curve is a distinct sine wave and the amplitudes are very uniform.
The aim of HRV biofeedback is to increase heart rate variability, specifically its amplitude. In other words, to maximize the difference between low heart rhythm and high heart rhythm in the interplay of inhalation and exhalation, rest and demands. Under demands and with uneven breathing,
HRV and its curve shape decreases significantly, as shown in the figure below:
In the above example, the curve is uneven, and the deflections are different. Especially from 6:30 and 6:50 the line is almost horizontal with almost no amplitudes.
If respiration is included, the eSense App offers various ways to visualize it and to define respiration in a certain rhythm. The coupling of heartbeat and respiration is greatest in most people when breathing at about 4.5 to 6.5 breaths per minute.
In the eSense app, you can do a free training or complete predefined procedures. The amplitude of HRV is measured and an increase is providing positive feedback, while a decrease provides negative feedback. A change in breathing is also linked to feedback.
 Lehrer, P. M. (2013). How does heart rate variability biofeedback work? Resonance, the baroreflex, and other mechanisms. Biofeedback, 41, 26-31.
For feedback, there is, for example, a video, that continues to run in the positive case (stops in the negative case), music, whose volume changes, tones, which change pitch, vibration of the Smartphone and much more. Of interest is the function for controlling a smart light bulb (Philips Hue or Magic Blue), whereby heart rate variability is reflected in the change in color and brightness of one or more lamps. You can use your stress level to illuminate an entire room.
A biofeedback training consists of four training stages. Plan about 60 to 90 minutes for the first session, during which you can do the training undisturbed and in one session. Detailed instructions can be found in the chapter, “Training sequence.”