source: own experience with the active 2 with side loaded apps and other firmware, the functions have been around for a long time.
ECG: a small current is applied to the wrist, with the other hand you make contact with the on / off button so that the current flows from the wrist through the chest to the other hand.
For pure rhythm disorders such as heartbeats that are skipped or when it beats irregularly, this is sufficient because you only need to know when the pulse happens, but it is also the only thing that one checks for, so take into account that everything but checks everything (ditto with Apple) There is far too much noise on the signal to analyze the QRS complex, although it is sometimes visible if there are large deviations. (from a medical point of view, this happens with sensors that are glued to specific places with conductive gel, you cannot compete with that with a finger and a watch that sits against the skin)
In practice, it mainly produces worried people who have very bad measurements because they have absolutely no idea what they are doing or how it works.
The blood pressure measurement works by studying the skin with high detail under light to get a view of the blood flow, the same technique with which the heart rate is determined very accurately, but for blood pressure the measurement will look in a lot more detail, which means that you have to sit completely still, talk. is enough to get the “try again” message. It is certainly not the case that you have continuous blood pressure measurements, only when you take them yourself. With this, the watch can mainly determine what the pulse pressure is, the difference between top and under pressure, but what the top and under pressure is correct, the watch needs a frame of reference for that. That means that before you can use this you need a classic blood pressure meter with which you have to measure several times together with the watch so that the watch has that frame of reference, after which the watch can do it on its own.
That works fairly accurately, but there are serious limitations, for example, the watch can only carry out the blood pressure measurement for the person it was taught to & very important, the watch must be recalibrated regularly compared to a classic blood pressure monitor, every 4 weeks (after that he refuses to take any measurements). Another problem is that if the blood pressure is suddenly much higher or much lower than usual, the watch suddenly dares to be seriously wrong. Probably because the frame of reference is suddenly no longer correct, for example because the blood has become thicker due to insufficient fluid intake.
In practice, if you want to use this, you should in any case purchase a decent blood pressure monitor to perform the continuous calibration, know how to use it and you better just always use that regular blood pressure monitor, it will not complain “measurement failed again once “, measures much faster, always measures accurately, does not require continuous calibration and is more credible to the doctor. The only advantage of the blood pressure monitor in your watch is that you always have it with you. It is useful to keep track of all blood pressure measurements in the Samsung health app.
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