It's actually quite simple. According to the principle of human bionics, the parameters of human heartbeat and heat consumption are reflected in time by high-tech means. In addition, according to my personal research, electronic products such as pedometers are actually simple in principle, but they contain many scientific and technological components. If you are a thoughtful person, you will naturally understand the mystery here. In line with the principle of not breaking things, I suggest you open it and have a look, and you will be suddenly enlightened. ~