A device, such as an implantable cardiac device, and methods for determining heart rate recovery of a patient after exercise. Specifically, the method includes identifying a first heart rate indicative of exercise, a second heart rate indicative of a slow-down in exercise, and using the first and second heart rates to determine a measure of heart rate recovery. The first heart rate may be identified when a heart rate measurement and/or an activity level exceeds a predetermined threshold. The second heart rate may be identified based when a heart rate measurement and/or the activity level falls below a predetermined threshold. The device includes hardware and/or software for performing the described methods.