The principle of the heart rate meter is to feel the change of myocardial potential through the strap worn on the chest, and then transmit it wirelessly to the watch worn on the wrist, and provide the change of heart rate per minute through technical functions such as amplification. Therefore, the electrodes that feel the change of myocardial potential are all inside the strap. Originally, I thought I could wear a watchband casually, just like the electrocardiogram examination in the hospital, as long as some of it comes into contact with the skin on the body surface before the heart.

When in use, the strap is first tied to the chest. According to the instructions, the two sides must be symmetrical. I'm worried that it may be uncomfortable if it's too tight, and it may fall off if it's too loose. So I was wondering if I could hang it on my right chest, but this one doesn't meet the requirements. It is required to be placed symmetrically on both sides of the chest. Some, like bras, may be uncomfortable at first, but they can be adapted gradually by adjusting the tightness.

After wearing the strap, you can use it. By default, the heart rate meter displays the current date, time and name. Names don't support Chinese, only Pinyin can be used.

You can change it to your own name by setting it. The heart rate meter1* * has five buttons, two on the left: time setting. Three on the right: middle managers, and the other two are up and down. It is very simple to use. Press and hold any key for 3 seconds to enter the heart rate counting state (the same as sigma's code table). After entering the state, if you receive the signal from the strip electrode in the chest, the villain on the right side in the middle of the dial will start running, and the largest number in the middle is the instantaneous heart rate. First, the training time is displayed, and the time unit is calculated in milliseconds. There are two triangular arrows on both sides of the time, indicating that there is a menu below. The adjustment button can display training time, lap timing, setting, time and heart rate respectively. When single lap timing is selected, the function of the corresponding top button on the right becomes the start button, and pressing it again will start the timing of each lap. At the same time, the button will become a stop button, and pressing it again will end the timing. Under the heart rate menu, there are four options: average heart rate, maximum heart rate, kilocalorie and total kilocalorie, which can be viewed separately. At the same time, the top of the dial shows the range of the current heart rate, which is divided into three sections: HZ (fitness zone), FZ (fitness zone) and PZ (strength zone). The heart rates of these three sections can be set under the setting items. Under these items, click the Manager button on the right at any time, and it will return to the default display at the beginning.

So although there are a lot of contents displayed, it is very simple to use, so it is very convenient. In use, it was found that the heart rate count did not start immediately after wearing the strap on the chest, especially in dry environment, it may take more time to feel the change of myocardial potential.

About waterproofing: The instructions say that this heart rate meter has waterproof function, and swimming on the water surface is no big problem. However, from the battery point of view, it is estimated that it is no problem to deal with ordinary rain and snow, just like the sigma code watch I use, but if it is soaked for a long time like swimming, the waterproof function is very general, so I dare not use it when swimming.