It uses only the wrist-worn device that reads the electronic signal released by the heart through the fingers pressed on the device for a given length of time. The two-part heart rate monitor on the other hand is composed of the strap and the wrist unit. The belt strap reads the heart rate measurement and acts as a transmitter. Since heart rate is very important during training, Reebok heart rate monitor assures you that every time you set yourself on training, you could get the most accurate heart rate reading anytime you want to. This would give you the idea of the status of your heart so if any discrepancy occurs, you would know and would be able to do something about it. The main problem here is that most manufacturers require you to send back the belt chest to recharge the battery. The point however is to ensure that you get a belt chest heart rate monitor with battery that could serve you for years. Most heart rate monitors manufactured today are designed for male users. Since heart rate monitor is usually worn both on the chest and on the wrist, the wrist unit also serves as a regular sports watch which you can use whenever you go either on a short supermarket errand or an afternoon walk in a park. Heart rate monitor is truly a great help during exercise and with all other purposes it serves, the heart rate monitor makes it easier to tract your cardio measurement and more. Some would have much while some have less that still depend on the type of heart rate monitor. Others are computer compatible which means you can store the data of your every workout on your computer for easier monitoring and better analysis and progress tracking. The type of heart rate monitor with this feature is much expensive. In order for this wave to travel, the doppler fetal heart rate monitor is aided by particular liquid often a lotion, oil or water. The liquid is applied on the mother s belly that would let the sound waves to travel from the heart of the baby across the belly through the monitor. The doppler fetal heart rate monitor can be used on expectant mothers carrying as early as 10-12 weeks old fetus to the moment you are about to give birth.