Clinical Research Directory

Trained vs. Untrained: Lower Extremity Pressure Changes

Research shows that how well oxygen moves from the lungs into the blood (called lung diffusing capacity) is linked to a person's aerobic fitness and endurance training. People who exercise regularly often have different lung and heart responses than people who do not. The exact reasons for these differences are still unclear. This study will test one possible explanation: highly trained people may handle changes in the amount of blood returning to the heart differently than people who are not trained. We want to learn how the blood vessels in the lungs react when the amount of blood entering the heart changes, and how this reaction is affected by fitness level. To do this, we will change how much blood returns to the heart by applying air pressure around the legs, similar to a light vacuum. These changes are expected to be similar to what happens when someone moves from lying down to standing up.