Exercise and Weight Loss for Improving Mobility in Older Adults Who Are Obese

Inclusion Criteria: * Currently living in one of the counties surrounding Winston-Salem, NC * Sedentary (engages in fewer than 30 minutes of moderate structured physical activity for at least 10 minutes at a time each week) * Overweight or obese, as defined by a body mass index (BMI) greater than 25 * Fasting glucose level less than 140 * Documented evidence of an MI, PCTA, chronic stable angina, or cardiovascular surgery (coronary artery or valvular heart disease) within the 6 months prior to study entry or an ATP III diagnosis of the metabolic syndrome * Disability defined as self-reported difficulty with walking ¼ mile, climbing stairs, lifting and carrying groceries, or performing other household chores such as cleaning and yard work * Does not plan to move out of the county of residence for the duration of the study Exclusion Criteria: * Diagnosis of bipolar depression or schizophrenia (defined as self-reported treatment for these conditions) * Currently receiving lithium or neuroleptics * Evidence of unstable angina, symptomatic congestive heart failure, or exercise-induced complex ventricular arrhythmias * Resting blood pressure greater than 160/100 mmHg * Diagnosis of any of the following: Parkinson's disease; chronic liver disease (cirrhosis, chronic hepatitis, etc.); systemic rheumatic condition (rheumatoid arthritis, psoriatic arthritis, Reiter's disease, systemic lupus erythematosus, etc.); end stage renal disease; or other systemic diseases or abnormal laboratory values which would preclude participants from safely participating in the protocol or impair their ability to complete the study * Actively being treated for cancer (other than non-melanotic skin cancer) * Significant visual or hearing impairment that cannot be corrected and results in the inability to use the telephone or hear normal conversation * Currently participating in or planning to participate in another medical intervention study * Current alcohol abuse disorder or consumes more than 21 alcoholic drinks per week * Unable to walk without assistance * Unable to speak or read English * Judged by the clinic staff to be unsuitable for the trial for any reason