Coherence

Monitor heart rate during breathing at a preset respiratory period. IMPORTANT NOTICE: !!! THIS APP IS FOR EDUCATIONAL PURPOSES ONLY !!! !!! THERE IS NO WARRANTY AND NO MEDICAL RELIANCE ON ANY DATA !!! !!! CONSULT A DOCTOR OR A HEALTHCARE PROVIDER FOR MEDICAL ADVICE !!! Breathing deep regular and slow will influence the heart rate known as "Respiratory Sinus Arrhythmia" (RSA) . During inhalation, the chest cavity expands and the thoracic pressure lowers thus fills the lungs with air, but also leads to a temporary lowering of arterial blood pressure. Through a mechanism called baroreflex the autonomic nervous system will respond with an increasing of the heart rate in order to keep homeostasis. During exhalation phase, the same mechanism will lead to a decreasing of the heart rate. Breathing at a period of about 12 seconds (5 brpm) will cause a "coherent" heart rate change for most people, meaning the inhalation and exhalation phases of breathing will match the increase and decrease of heart rate changes (RSA). However the coherent respiratory rate is individual and may vary with the current mood. If the breathing is to fast, the RSA will lag behind the respiratory phases and if the breathing is too slow, the RSA will rush ahead the respiratory phases. The current heart rate is displayed at the left center in red [bpm]. The RSA as the red curve show you how "coherent" the heart rate changes are with the breathing as the blue sinus wave. Try to breathe with the blue sinus wave, as it goes up and down at the ruler on the right. The red curve should match the blue wave as much as possible. If the red curve is shifted to the left/right in relation to the the blue wave, the preset respiratory period is too long/short , and will be signaled with a "-"/"+" sign after the respiratory period time on the right center in blue [s], indicating to decrease/increase the period time with the page down/up buttons, swipe down/up or in the app settings via Connect IQ. The current RSA will be shown on bottom [bpm]. Likewise the VO2max for runners, the RSA is a core size for the ability to relax. There are scores every 6bpm that classify your actual RSA value. With practice and deeper calmer breathing, the value can be improved. As the VO2max, the RSA also depends on your age (Please give me feedback on your RSA values and age, to enhance the app). The collected activity data can be observed in the Garmin Connect App. There are charts showing the heart rate changes, the respiratory phase, the RSA, the waveform coherence and the phase shift. Average values can be found in the summary. I highly recommend an ECG chest strap, because the heart rate will have a much better quality. Be aware, that some chest straps have a motion sensor, that will turn the device of if you do not move.

DUE TO THE LOSS OF THE SOURCE CODE, THIS APP IS NO LONGER BEING DEVELOPED. Version 1.6.1: - Configurable vibration (4 x short) on session end - More accurate timer Version 1.6.0: - Introduced RSA Scores: 0-6 bpm = Little, 6-12 bpm = Fair, 12-18 bpm = Good, 18-24 bpm = Excellent, 24+ bpm = Superior - Respiratory period will be displayed in red with a +/- sign to signal that you should increase/decrease the period time - The heart rate curve is normalized, so that the amplitude is always equal to the blue respiratory sinus wave, ragardless of your RSA. - Enhanced phase shift calculation. - Languages: Support for German and Spanish (OMG Please give feedback) Version 1.5.0: Settings "Autosave Session Time": if set (greater than 0) the session will be stopped and saved automatically after the preset minutes. The Timer will show the remaining time in red. Key control 1. Standard behavior of start/stop key: Starts a new or paused session, and shows a menu during a running session: "Continue", "Save", "Discard". 2. Lap key will unset the "Autosave Session Time" for this session. Displayed Values: The RSA [bpm] (green) and phase-shift [s] (pink) will be displayed on the bottom as an average value for the current respiratory phase and inhalation / exhalation ratio. Version 1.4.0: Swipe Support 1. Swipe Up/Down to increase/decrease respiratory period time (please note: the assignment of hardware buttons Up/Down has also changed to increase/decrease) 2. Swipe Right/Left to increase/decrease percentage inhalation phase Data Summary 1. Workaround for iPhone Bug (wrong presentation of precision for numeric values) Version 1.3.0: Connect IQ Settings 1. Dark Mode - Dark colors 2. Sleep Timeout - Sleep Mode (blank screen, only background, no screen refresh) after N seconds. Smallest value 10 seconds. Countdown on screen 10 seconds before. During countdown and during sleep mode, hit any key to reactivate display. Data Summary 1. Coherence Phase - Quality of synchronicity between respiratory phases and heart rate changes. 100% = concurrent, 0% = contrary Version 1.2.1: - Fix for Venu 2 / Bitmap Issue Version 1.2.0: Signaling change of breathing phases: 1. through a message ("breathe in" / "breathe out") 2. through vibration (1 x long = breathe in / 2 x short = breathe out) Signaling can be configured as application settings via Connect IQ. The vibration strength can be set from 0% (= off) to 100% (maximum). Default is message = ON and a vibration strength of 8% Adjustable breathe in / breath out phases as percentage of the whole respiratory cycle (e.g. a "breathe in phase length" of 41% will divide a whole respiratory cycle of 11s into 4.5s breathing in and 6.5s breathing out ;). The percentage is an integer from 0% to 100%. Regardless of crazy settings, the minimum of 1s is guaranteed for both breath in and breath out phase. The splitting in seconds will be found in the summary of the activity in the connect app. Actual, there is a problem with the Connect App showing the right precision, however the Garmin Connect web page will show the precise splitting. Default value are equal balanced breathing phases (50% / 50%). The percentage configuration was chosen instead of two separat values, to ensure an easy increase / decrease of the respiratory period with the page down / page up buttons during a session while keeping the breathing phase ratio.