How should you use a heart rate monitor

 Measure your heart rate before, during and after work outs and write it down. Monitors can be worn as a strap across the chest, on the wrist and even on the head, and by measuring your heart rate can help you exercise at the right intensity. Most don't have a display, so you'll need to connect your monitor with a sports watch or smartphone app to see your heart rate.

They can be used around the chest, the wrist, and head. If you are planning on working out, this is a good way to measure the intensity you will work out out on.

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