A system and method are provided for measuring biometric signals. The system includes a first electrode, a second electrode and a circuit. The first electrode forms at least a portion of a first belt configured to be placed at least partially around a torso of a subject. The second electrode forms at least a portion of a second belt configured to be placed at least partially around the torso. The circuit is configured to measure a voltage between the first electrode and the second electrode. The first and second electrodes are arranged to determine the respiratory effort of the subject. The first or second electrode includes a capacitive electrode with a flexible structure including an insulated conductor. The insulated conductor is insulated such that the conductor does not come in direct contact with skin of the subject when the first or second electrode is placed on the subject.