Heart rate belts

Pulse belts – also called chest belts, heart rate belts or HRM (Heart Rate Monitors) – are popular in sports and with people who like to exercise accurately. They're ideal in combination with sports and smartwatches. However, there are also models that can be used without a watch thanks to their internal memory. A heart rate refers to the number of heartbeats per minute, during an exercise routine for example. But why would you need a heart rate belt when smartwatches already measure the pulse on your wrist? Pulse belts are much more accurate, while sports watches measure additional data (speed, distance, stride length, cadence, calorie consumption, altitude, etc.).

How differently do smartwatches and pulse belts measure?
Watches use optical heart rate sensors on your wrist. They recognise the blood pulsing through your veins. Each heartbeat pumps oxygen into the blood, causing the blood vessels to dilate. Green LED lights measure the oxygen change in your blood vessels and convert the data into heartbeats. This indirect measurement lags slightly behind the actual heart rate. In addition, the watch moves along the wrist depending on the intensity of your routine, sweat and arm movements on top of losing contact with your skin. Clocks therefore measure less accurately and are slower in data acquisition. However, they're more comfortable to wear, especially during longer training sessions. Pulse belts are worn around the chest and measure the electrical activity of the heart directly. The sensor lies on the sternum in close proximity to the heart, measuring the electrical signals and converting them into a heart rate measurement. The heartbeat itself is registered, not the delayed change of oxygen. As a result, a heart rate belt is more accurate and reliable than optical measurement on the wrist. Other reasons for increased accuracy: the sensor is located in the immediate vicinity of the heart and the elastic belt adapts ideally to the torso without losing contact with the skin. Another advantage is that most pulse belts are battery operated and don’t need to be recharged.

Why use heart rate data?
The heart rate can be analysed after a training session. Heart rate measurements provide valuable insights into your general state of health. Particularly in endurance sports (running, cycling and swimming), correct analysis of the data can provide valuable information to optimise exercise and improve fitness. It doesn't matter whether you're a novice, advanced amateur or professional athlete, a heart rate belt is a good idea in all situations. Training within the correct heart rate zone is the backbone of any healthy and targeted training routine. For beginners, heart rate data can help discover how under- or overstrained you feel when training in a certain heart rate zone. With increasing training frequency or intensity, progress can be detected correspondingly quickly. For advanced and professional users, pulse data can help set goals and better assess and crack their own limits. Depending on the heart rate zone (also called heart rate frequency, i.e. an individual interval between two pulse points) a different training effect is achieved.

What does science say?
A scientific study compared the accuracy of three measuring methods during training: ECG, pulse belt and a wrist sports watch. The medical ECG provides the most accurate measurement. Heart rate belts can reach up to 99.6% of ECG values, whereas sports watches with optical measurement on the wrist can only reach between 67 and 92%.