Exposure to microgravity can result in stiffening of the heart and arteries, leading to orthostatic intolerance (not being able to stand), reduced exercise capacity and decreased blood flow. Research shows that aging and physical inactivity produce similar cardiovascular effects. NSBRI Postdoctoral Fellow Dr. Shigeki Shibata has designed a project to assess the effects of aging and microgravity exposure on the interaction between the heart and the blood vessels. The project will also determine the optimal amount of physical activity to prevent the changes in how much blood the heart pumps and how the blood vessels distribute it to the tissues.
The project uses two different groups of subjects, covering a wide age range, to study the effects of varying amounts of exercise on the stiffening of the heart and arteries. One portion of the study involves healthy young individuals undergoing five weeks of bed rest to simulate the effects of microgravity on the body. The second part of the study involves statistical comparisons of healthy senior citizens over a broad range of age and fitness levels. Findings from this project will determine the effectiveness of exercise to prevent vascular problems related to prolonged microgravity exposure or the deconditioning associated with aging.