A monitoring apparatus (4) monitors a users heart rate and/or heart rate variation. The apparatus includes a capacitor (22) which is positionable on or near a body part of a person, for example a persons limb, for example an arm (3), such that an electrical capacitance of the capacitor (22) is influenced by blood pressure pulses of blood running through the body part. The apparatus (4) also includes a data processor (26) for determining the heart rate and/or heart rate variation from changes in the capacitance of the capacitor (22).
