The purpose of this study is to determine the effects of exercise and cardiorespiratory fitness on age-related brain changes.

The mission of the KU Brain Aging Project is to promote healthy brain aging. How the brain changes with age is not well-characterized and even less is known about the factors influencing the rate of brain aging. Thus, we are using MRI scans to examine the structure of the brain in relation to important lifestyle factors. This will allow us to better understand the processes influencing the brain as it ages. In turn, this will help identify specific ways to promote healthy brain aging and, perhaps, prevent the onset of Alzheimer's disease.

Participants complete 4 visits over several months. The first visit entails a clinical evaluation and memory testing involving the use of paper and pencil testing. The second visit is an MRI brain scan which lasts approximately one hour. The third visit involves drawing blood for laboratory testing and blood banking for future lab studies, lasting roughly 4 hours. The glucose tolerance test is administered. The fourth and final visit is an assessment of the participant's metabolism and exercise testing. This visit lasts approximately two hours.

Inclusion Criteria:

• Age 65 years or older
• Healthy male or female
• Normal control volunteers and early Alzheimer's disease patients
• Clinical Dementia Rating of 0, 0.5, or 1.0
• On stable doses of medications

Exclusion Criteria:

• Unstable angina
• Schizophrenia
• Clinical signs of depression; major depression; mental health disorder; nervous system disorder
• Significant visual/auditory impairment
• Significant system illness; cancer
• Pacemaker/metal
• Thyroid problems
• Kidney dialysis
• Organ transplant
• Alcoholism
• Heart surgery
• Insulin