Clinical Research Directory

Inclusion Criteria: * Veterans, aged 50 to 90, of any racial or ethnic group * Diagnosis of single or multi-domain amnestic MCI using criteria per National Institute on Aging/Alzheimer's Association Guidelines * Available informant for completion of the Clinical Dementia Rating Scale * Visual and auditory acuity to allow neuropsychological testing * Willingness to participate in clinical trial for 14 months (8-month treatment phase, 6-month no-contact follow-up phase) * Musculoskeletal illness or injury (i.e., osteoporosis, degenerative disc or joint disease, arthritis, obesity) * Approval by Primary Care Provider to participate in water-based physical exercise Exclusion Criteria: Psychiatric Exclusions * Current, uncontrolled severe psychiatric disorder, such as Bipolar I, Schizophrenia, or Major Depressive Disorder as determined by the Mini International Neuropsychiatric Interview (MINI) * Diagnosis of dementia, Clinical Dementia Rating Scale (CDR) \> 0.5; modified Hachinksi score 4; or delirium. Those Veterans with scores indicative of dementia (CDR \> 0.5, modified Hachinksi 4) will be referred to the Memory Disorders Clinic at VAPAHCS for a full diagnostic work-up Medical Exclusions * History of neurological (e.g., multiple sclerosis, seizure disorder, stroke,) or system illness affecting CNS function (e.g., liver failure, kidney failure, congestive heart failure, systemic cancer) * Acute illness or unstable chronic illness, e.g., history of severe liver disease (cirrhosis, esophageal varices, ascites, portal hypertension, hepatic encephalopathy) * Current severe cardiac disease (e.g., uncontrolled atrial fibrillation, defined as mean 24 hour heart rate \>85 beats/min, or 24 hour maximal ventricular rate \>150 beats/min; uncontrolled ventricular arrhythmias, defined as recurrent ventricular tachycardia \>3 beats in succession, or 24 hour PVC count \>20%; active pericarditis or myocarditis; Class III/IV heart failure and / or ejection fraction \< 20%; thrombophlebitis; pulmonary disease with a drop in O2 Sat with exercise to 90% without oxygen; embolism within past 6 months) * Inability to participate in an exercise stress test * Inability to read, verbalize understanding and voluntarily sign the Informed Consent