Some embodiments can include a device for detecting heart rate. In a number of embodiments, the device can comprise at least one capacitive displacement sensor coupled to a strap. In many embodiments, the at least one capacitive displacement sensor can comprise two electrodes. In some embodiments, the two electrodes can comprise an outer transmitting electrode and an inner receiving electrode. In various embodiments, the at least one capacitive displacement sensor can detect a pulse by producing a signal associated with a distance change between a skin of a wearer of the device and the at least one capacitive displacement sensor. Other embodiments of related apparatuses, methods and systems are also provided.
