This is a single site, randomized exercise trial with individuals at least 50 years of age living with HIV who experience suboptimal cognition. The overall goals of this proposal are to determine whether 16 weeks of structured high-intensity interval training (HIIT) can overcome vascular and cognitive impairments (Aim 1) to a greater extent than continuous moderate exercise. Additionally, investigator will seek to identify barriers to engagement in exercise and the participants' perceptions of the study and exercise interventions (Aim 2). This study will enroll 60 participants in Birmingham, Alabama. Data collection will occur at each visit, with baseline data collected at the initial visit with a 3-month follow-up occurring following completion of the intervention.

This is a single site, randomized exercise trial with individuals at least 50 years of age living with HIV who experience suboptimal cognition. The overall goals of this proposal are to determine whether 12 weeks of structured high-intensity interval training (HIIT) can overcome vascular and cognitive impairments (Aim 1) to a greater extent than continuous moderate exercise. Additionally, investigator will seek to identify barriers to engagement in exercise and the participants' perceptions of the study and exercise interventions (Aim 2). This study will enroll 60 participants in Birmingham, Alabama.

Vascular function will be measured using pulse wave velocity. Cognition will be assessed using the full neuropsychological battery. Additionally, perceptions of exercise and the study as well as barriers to engaging in exercise will be determined through the analysis qualitative interviews.

The overall hypothesis is that HIIT will result in greater enhancements in vascular and cognitive function. The investigators expect that individuals randomized to HIIT will result in greater satisfaction with the protocol. Based on the data collected, the investigators seek to develop tailored intervention to promote successful aging among older people living with HIV.

Inclusion Criteria:

• Age 50 years and older
• Sedentary lifestyle, defined as < 150 min/wk moderate physical activity as assessed by CHAMPS questionnaire
• Neurocognitive Impairment (as assessed using the BRACE+
• Prescribed HIV ART for ≥ 12 months, with no current use of older drugs with established mitochondrial toxicity
• Able to speak, read, and write in English
• Willingness to participate in all study procedures

Exclusion Criteria:

• Diagnosis of mitochondrial disease
• Active substance abuse or factors preventing compliance or safety
• Uncontrolled hypertension, defined as resting BP > 150/90 mmHG
• Chronic kidney disease
• Severe cardiac disease, including NYHA Class III or IV congestive heart failure, clinically significant aortic stenosis, history of cardiac arrest, use of a cardiac defibrillator, or uncontrolled angina
• Acute myocardial infarction identified by medical history and ECG
• Pulmonary disease requiring the use of supplemental oxygen
• Poorly controlled diabetes
• Neuropsychologically Intact
• Orthopedic problems that limit ability to perform exercise
• Simultaneous participation in another intervention trial

Participant-level deidentified data will be preserved through deposition of the data in a controlled public repository. All aggregate datasets that can be shared publicly will be deposited in the NIH/NIA Repository, National Archive of Computerized Data on Aging (NACDA).

Data will be made available no later than the time of an associated publication or end of the funding period, whichever comes first. NACDA guarantees data will be made available for ≥10 years

De-identified individual participant data will be deposited into NACDA as restricted, which limits access to the data to qualified investigators with who must sign a data use agreement. NACDA requires users to submit a data use agreement. NACDA will review the data request for completeness and determine if an IRB approval is needed. Anyone who has submitted an approved data request and signed data use agreement on NACDA will be given access to the data without cost, for a set period.