Everyone should be exercising at their optimal or target heart rate in order to gain the most benefit from their exercise plan. However, there are many cases where you can do significant damage if you exercise beyond where your target heart rate should be.
Moreover, there is a huge variety of Heart Rate Simulator at pronktech.com/product/spo2-simulator-pulse-oximeter-tester-oxsim-flex-ox-2 which you can check.
Too much exercise can actually slow down your metabolism, just like when you're not eating enough. If you don't have enough energy intake and, at the same time have excessive energy output, you may start to burn healthy lean muscle mass tissue for energy.
Using a wireless heart rate monitor, you can check your heart rate as you steadily increase the intensity of your exercise during the warm-up period until you attain your target heart rate. (Based on age, weight) You can monitor to make sure that you are maintaining your target heart rate for the required 20-25 minutes, and then gradually lessen your intensity for your cool down. It also provides flexible control of your all simulation.
Not only does the heart rate monitor, enable you to achieve your target heart rate more accurately, but it also reminds you and guides you through the VERY important, but often ignored warm-up and cool-down periods.