This study investigates how breathing patterns during moderate exercise impact brain blood flow in older adults. The goal is to explore potential strategies for preventing cognitive decline by understanding cerebral autoregulation. We aim to determine whether altering breathing during exercise improves brain blood flow more effectively than standard breathing. We also compare how different types of exercise (treadmill vs. cycling) impact this response. Findings from this study could contribute to developing interventions that support brain health and potentially delay the onset of dementia.
Participants in this study will be asked to attend two separate laboratory visits, during which a variety of physiological assessments and exercise tasks will be completed. Before each visit, participants are advised to avoid heavy meals for at least four hours to minimize the risk of gastrointestinal discomfort or dizziness during the exercise. At the beginning of each session, informed consent will be confirmed, and participants will complete questionnaires that address their physical activity habits, overall wellbeing, and relevant health history. Female participants of childbearing age will undergo a urine pregnancy test before the body composition assessment.
The first part of the assessment involves measuring body composition using a dual-energy X-ray absorptiometry (DEXA) scanner. Participants will lie still on a table while the scanner takes a full-body image lasting approximately five minutes. Additional anthropometric measurements such as waist and hip circumference and body weight will also be recorded. Following this, vital signs including heart rate and blood pressure will be assessed. Heart rate will be monitored via a wireless chest strap, and blood pressure will be measured with an inflatable cuff on the arm, similar to a typical clinical check-up.
Next, participants will perform a lung function test known as spirometry. While seated, they will wear a nose clip and blow into a mouthpiece, exhaling as forcefully and completely as possible. This test evaluates respiratory strength and capacity and may cause brief dizziness due to chest pressure, which typically resolves quickly. The main portion of the study involves aerobic exercise sessions. Participants will complete two 20-minute moderate-intensity workouts, either walking on a treadmill or cycling on a stationary bike. The type of exercise and breathing pattern; either combined breathing or nasal-only breathing, will be randomly assigned and alternated across the two visits.
While participants are exercising, researchers will assess cerebral blood flow using ultrasound sonography. A small ultrasound probe, applied with warmed gel, will be gently placed on the side of the participant’s neck to measure blood velocity in the cerebral arteries. At the same time, participants will wear a blue respiratory mask connected to a computer system to analyze breathing patterns and gas exchange. These tools will help determine how different breathing techniques influence brain blood flow during exercise.
After the exercise, participants will be monitored for any signs of discomfort such as muscle soreness, lightheadedness, or headaches. They may rest as needed. All procedures are supervised by the Principal Investigator, Dr. Jose M. Moris, who will respond to any signs of medical concern and call emergency services if necessary. Participation in the study is entirely voluntary, and individuals may stop at any point without penalty. This comprehensive, controlled protocol is designed to explore how breathing alterations during exercise may influence brain perfusion and potentially support strategies for maintaining cognitive health.
Summary
| Component | Duration | Key/Tool Measure |
| Questionares | 15 minutes | Wellness and physical activity surveys |
| Body Composition (DEXA) | 5 minutes | Whole-body X-ray scan |
| Vital Signs | 5 minutes | Heart rate monitor, BP cuff |
| Spirometry (Lung Test) | 10 minutes | Nose clip, spirometer |
| Excercise & Brain Flow | 20 minutes | Treadmill or bike + ultrasound + mask |
Contact Us
Dr. Jose M. Moris
📞 (956) 326-3288
📧 jose.moris@tamiu.edu
📍 TAMIU Campus, CNS 302-C
IRB Contact for participant rights
Dr. Elizabeth Terrazas-Carrillo (Chair)
irb@tamiu.edu | (956) 326-2656
Acute Effect of Hypercapnia on Cerebral Autoregulation in Older Adults 