Physical Fitness, Cardiovascular and Brain Health

The goal of this study is to determine if aerobic exercise or progressive muscle relaxation is associated with changes in cardiovascular health, brain function, and cognition.

Inclusion Criteria: * Sedentary adults Participants will be classified as sedentary if they have not engaged in regular physical exercise for at least one year prior to study enrollment. * Ages 45-65 * Normal blood pressure or Borderline or stage 1 hypertension Borderline hypertension will be defined as systolic blood pressure between 120-139 mmHg and/or diastolic blood pressure between 80-89 mmHg. Stage 1 hypertension will be defined as systolic blood pressure between 140-159 mmHg and/or diastolic blood pressure between 90-99 mmHg. Exclusion Criteria: * Signs or symptoms of chronic heart disease * Smoking (current or within the past 6 months) * Peripheral artery disease (ankle-brachial index\126 mg/L) * Orthopedic problems that would prohibit participants from participating in exercise. * Axis I psychiatric disorder * Magnetic resonance contraindications * Baseline Intellectual Quotient \< 70 * Below chance performance on the practice items of the cognitive tasks * Evidence of large vessel stroke on magnetic resonance imaging