This app makes it easy to control your breathing rate by regulating the length of your inhalations and exhalations, as well as the pause between them. For example, you can use it to practice “box breathing” specifically to reduce stress and achieve a state of calm in no time. Navy SEALs use this breathing technique to remain calm and focused in stressful situations. It involves breathing in evenly, holding your breath, breathing out, and holding your breath again. Using the menu, you can set the duration of inhalation and exhalation to 3, 4, 5, 6, 7 or 8 seconds, and the hold time to 0 to 8 seconds. You can also set a timer for 3, 5, or 10 minutes. It is possible to activate the heart rate display, signal tones (if supported by the watch), and vibration. If you open the menu in “Breathe” mode (by pressing the menu button, e.g., on the Fenix 8, hold down the Menu/UP button. The menu on the Venu 4, Venux X1, and Vivoactive 6 can only be opened once box breathing has been started.), you have the following setting options: - Inhale Duration (3, 4, 5, 6, 7 or 8 seconds) - Hold after Inhale (0 to 8 seconds) - Exhale Duration (3, 4, 5, 6, 7 or 8 seconds) - Hold after Exhale (0 to 8 seconds) - Timer (off, 3, 5, or 10 minutes): Duration of box breathing - Heart rate (on/off): Heart rate display during box breathing - Sound (on/off): Beep during box breathing (if supported by the watch) - Vibration (on/off): Vibration during box breathing - Exit A second feature of the app is the 4-7-8 breathing technique. This is a relaxation method based on Indian pranayama (yoga breathing) and made famous by physician Dr. Andrew Weil. It is often referred to as a “natural sedative for the nervous system.” It serves to immediately reduce stress, help you fall asleep, and control anxiety and panic by lowering your heart rate and stabilizing your blood pressure. The app guides you through 6 rounds of this breathing technique (settings cannot be changed in this mode in order to guide breathing in a simple and targeted manner), in which you inhale deeply through your nose for 4 seconds, hold your breath for 7 seconds, and exhale through your mouth for 8 seconds. A third feature is Breath-Hold. The goal here is to let a freediver stay underwater as long as possible. By pressing the Start/Stop button or tapping the screen, the diver descends. Tapping a second time brings the diver back up. Try to hold your breath until the diver reaches the surface again. If you need to take a breath before then, tap the screen or the Start/Stop button again. That means you overestimated your ability. A high-score list shows your best times. This is a fun way to increase your CO₂ tolerance and strengthen your breathing muscles. However, only do this while sitting or lying down, never in the water! If you like this app, I'd really appreciate a positive review =)