Active Gains in Brain Using Exercise During Aging

Inclusion Criteria: * Men and women 65 - 80 years. * Able to speak and read fluent Spanish. * Living in community during the study. * Reliable means of transportation. * Being physical inactive (i.e., not to be participating in the last 6 months in any resistance exercise program, or accumulating less than 600 METS/Week of moderate-vigorous physical activity). * Classified as cognitively normal according to Stics-m MMSE and MOCA tests. Exclusion Criteria: * Ambulatory with pain or regular use of an assisted walking device. * Medical contraindication for inclusion in an exercise program. * Neurological condition (Multiple Sclerosis, Parkinson Disease, Dementia) or brain injury (traumatic or stroke). * Current diagnosis and treatment of a DSM-V Axis I or II disorder including major depression and seeing a psychologist, therapist, or psychiatrist. * History of major psychiatric illness including schizophrenia, general anxiety disorder or depression (GDS-30\>=15). * Current treatment for congestive heart failure, angina, uncontrolled arrhythmia, deep venous thrombosis or other cardiovascular event. * Myocardial infarction, coronary artery bypass grafting, angioplasty or other cardiac condition in the past year. * Current or previous treatment for any type of cancer. * Type I Diabetes or uncontrolled Type II Diabetes defined as Insulin dependent or Hba1C greater than 10. * Recent treatment for alcohol or substance abuse. * Presence of metal implants (e.g., pacemaker, stents, joint replacement) that would be MRI ineligible. * Claustrophobia. * Color blindness. * Diagnosis of COVID-19 with hospitalization in intensive care unit. * Any other consideration that interferes with the study aims and could be a risk to the participant, at the discretion of the researcher.