APPROPRIATE - Rate Adaptive Pacing Sensor

Inclusion Criteria: * Meets or met current pacemaker implantation indications * Willing and capable of providing informed consent for participation * Receiving a dual-chamber pacemaker or previously received a dual-chamber pacemaker with active atrial and ventricular leads * Plans to remain in the long-term care of his/her enrolling physician and is available for study follow-up for three months post-enrollment Exclusion Criteria: * Mobitz II second degree heart block * Third degree heart block * Chronic atrial fibrillation or uncontrolled atrial arrhythmias within the past 90 days prior to consent * Neuromuscular, orthopedic, or vascular disability that prevents normal walking or weight carrying (e.g., intermittent claudication, arthritis, residual stroke weakness, need for a wheelchair or walker) * A symptom-limited exercise protocol is thought to be dangerous or contra-indicated, including but not limited to changing pattern of chest discomfort or uncontrolled arrhythmias * Pulmonary disease as defined by any one of the following: * Forced Vital Capacity (FVC) or Forced Expiratory Volume in one second (FEV1) \< 60% of predicted values * Use of two or more pulmonary inhalers * Use of supplemental oxygen * Chronic use of oral steroids for pulmonary disease treatment * Life expectancy is less than 12 months due to other medical conditions, per physician discretion * Has or indicated for an implantable cardioverter defibrillator (ICD) or cardiac resynchronization therapy-defibrillator (CRT-D) * Currently enrolled in another investigational study that would directly impact the treatment or outcome of the current study. * Younger than 18 years of age * Pregnant or planning to become pregnant during the study (method of assessment upon physician's discretion) * Unable or unwilling to comply with the protocol requirements