The Key to more Health: How to Check Your Resilience in Just 3 Minutes

From the 22nd day of our life, the impulse for the rhythm that will accompany us throughout our entire life begins – the heartbeat. Just as the eyes are the window to the soul, our heart represents the gateway to our vitality.

In addition to its lifelong, maintenance-free function, the range at which our heart can pump blood through our circulatory system is truly remarkable: at rest, our heart beats around 60 beats per minute (bpm). During sleep, the heart rate can decrease to as low as 45 bpm. When we are under maximum stress, our heart reaches an individual maximum frequency of around 200 bpm (rule of thumb: 220 bpm – age), and in cases of physical distress, such as respiratory diseases, an increased resting heart rate can be observed.

In addition to the autonomous function of the heart, it is also possible to consciously, or voluntarily, influence the heart rate – something we’ve known since James Bond escaped from the medical unit of MI6 (in Die Another Day he fakes his cardiac arrest). Admittedly, this is quite exaggerated, but there are medical reports showing that individuals were able to consciously stop their heartbeat for up to 5 seconds. Through deep and slow breathing, you can reduce your heart rate yourself. Try it out: breathe in slowly and deeply, then exhale slowly through lips closed as if you’re about to kiss (about five seconds per breath; repeat 12 times).

A Look Behind the Scenes

In everyday life, we hopefully rarely need to fake our death. However, the topic of “Return to Play” after an infection (referring to returning to work or physical activity) is an important consideration due to potential complications (e.g., myocarditis). Prolonged psychological and physical stress resulting from an imbalance between exertion and recovery can also lead to serious negative consequences for our health (e.g., burnout, overtraining), where we can’t rely solely on our bodily sensations. When we realize we’re getting sick or are already ill, it’s usually too late to take the right measures. So, what if we could know in advance whether recent stress is overwhelming us, if flu is on the way, or if we’re fully ready to perform again?

Heart Rate Variability (HRV)

HRV refers to the time interval (in milliseconds) between the peaks of successive heartbeats:

Example: Heartbeat 1 … | TIME 1 | … Heartbeat 2 … | TIME 2 | … Heartbeat 3 … | TIME 3 | … and so on…

The initially paradoxical thing about this is that the time intervals (in the example TIME 1, TIME 2, TIME 3) should ideally vary as much as possible. The more regularly the heart beats, the less recovered or more stressed it is.

There are two main methods to measure HRV, but I won’t bore you with the details, dear reader: 1. Electrocardiogram (ECG), 2. Photoplethysmography (PPG).

Important: The more accurately the heart rate can be measured, the more precise the detection of the peaks and, consequently, the analysis of the data. Nowadays, most high-end smartwatches and wearables include HRV measurement and analysis as standard features. However, these results and interpretations differ based on the mathematical methods used.

Clarity About Your Condition in Just Three Minutes

For training management, assessing mental and physical conditions before or after a workout is a crucial control element. During my time as a strength coach for the German national rhythmic gymnastics team, we used HRV to determine the intensity of training sessions.

However, HRV screening can also be a useful decision-making tool in everyday life. For example, that spontaneously chosen work-from-home day can help prevent an oncoming cold.

In daily use, HRV measurement is quite simple: wear a chest strap while in a semi-lying position, right after waking up, with a regular breathing rhythm for 180 to 300 seconds. Afterward, you’ll receive not only an assessment of your physical condition and guidelines for strength and endurance training but also an estimate of your biological age.