Chest strap HR monitors are based on simple but powerful technology. They measure electrical signals from your heart every time it beats. These signals are similar to what an ECG machine in a hospital records. The chest strap has sensors that stay close to your skin and pick up this electrical activity. Once detected, the signal is sent to a connected device — like your smartphone, smartwatch, or a fitness tracker — via Bluetooth or ANT+. The paired device then displays your current heart rate, tracks trends, and stores your workout data for future analysis.
