Systems, devices, and methods for providing a feedback signal to assist a patient in repeating a breath-hold at the same point in successive respiratory cycles. The tracking device includes: a spring-biased wheel a strap configured to wrap around a patient and having a segment configured to wind around a portion of the wheel when the patient exhales, and to unwind when the patient inhales and a processor configured to detect an angular position of the wheel and to present the patient with a corresponding feedback signal.
