Any serious medical condition for which exercise is contraindicated by the ACSM Current diagnosis of one of the following: psychosis, bipolar disorder, lupus, HIV, AIDS, IBS, Crones, Rheumatoid Arthritis or related conditions, cancer or treatment for cancer within the last year. Acute illness Terminal illness (not expected to live beyond one year) Unwillingness to provide informed consent Unwillingness to donate blood Receiving disability insurance Currently engaged in professional psychotherapy Currently engaged in regular exercise Pregnant or nursing in the past 6 months, or plans to become so within 12 months Enrolled in another study Member of household enrolled in the same study Residence outside of Marion County Residence relocation plans within 12 months Substance abuse Suicide ideation as indicated by the PHQ-9