How do we explore your stress and resilience level?

In addition to an empathetic approach, we also apply proper

science-based technology to evaluate your stress level.

The Stress Guide is so much more than just an app to evaluate your heart data. Rather, it combines innovative medical technologies with proven mindfulness techniques. And that is how we created your digital companion. We analyze your stress based on scientifically founded methods, as well as guiding you through relaxation exercises and positive habit building, so that you can enjoy a healthier life. Furthermore, the Stress Guide is certified as a medical product class I.

Which index values do we determine?

We measure various vital data to determine your stress level. The most important are the Stress Level and the Recovery Ability.

Stress Level

Your Stress Level is a heart rate index and is determined by the variability of the heart rate. It is an objective indication of how much stress you are currently under.

Recovery Ability

Your Recovery Ability is measured by the parasympathetic nervous system. This controls your body while at rest. The easier you are able to calm down, the higher your stress resilience is.

Energy Status

The Energy Status is also measured by the parasympathetic nervous system. Here, we determine how fast the change in your heart beats occurs, based on which we can detect whether your body is resting orĀ using existing energy reserves


How we determine your values

Our team has developed a patented technology that enables your Stress guide to measure your HRV using just your smartphone camera.

Depending on your device we use camera plus flash or the sensor to make your blood vessels visible to determine your heart rate variability. By placing your finger on camera or sensor, we can measure different indexes.

By illuminating your fingertip, the Stress Guide is able to detect and analyze changes in your blood vessels, which occur due to your natural heartbeat. When blood is pumped through your vessels they appear darker, whilst blood being pumped out leads to lighter vessels.

Based on these changes we detect your heartbeat. Consequently, our special algorithm analyzes the data obtained and determines your heart rate variability, which can tell us a lot about your stress.

Who has access to my data?

We do not share your personal information or measurements with anyone. Only you have access to your individual measurements. We only use aggregated statistics of all our users to further customize and improve our service to your needs.


The time interval between the heartbeats of a healthy heart is constantly fluctuating. Although these fluctuations can besmall, they indicate how well your body handles stress. The intervals over a given time period are referred to as your heart rate variability, or HRV.

A high HRV indicates that your body can cope well with stress. In contrast, a low HRV can be a symptom of fatigue, stress or even illness. There are many values that can be used to measure HRV, of which RMSSD und PNN50 are two.

Root Mean Square of Successive Differences (RMSSD):

Rhythmic Variability of the Heart (RMSSD) tells you how well your body is recovering from stress. It reflects how well the parasympathetic nervous system can help you to regenerate and recover. A high level of stress relief is partly due to a high RMSSD.


The PNN50 is the fraction of consecutive heartbeats with an interval greater than 50 milliseconds between them. Therefore, a higher PNN50 value shows that your heart rate has drastically changed in a short time period.

RSA Amplitude:

Respiratory Sinus Arrhythmia (RSA) Amplitude, sometimes referred to as the HRV amplitude, is the change of heart rate believed to be caused by breathing. We are measuring it by breaking the measurement into sections which match the expected breathing interval of our users – ten seconds in length – , calculating the difference between the maximum and minimum heart rate, and averaging the results found for each of the sections; AVG (Max – Min Heart Rate).

Start your journey to health and happiness


Kenkou GmbH

Torstrasse 177

10115 Berlin, Germany