This study aims to understand why people with chronic kidney disease (CKD) have trouble exercising and experience high blood pressure during activity. CKD is when the kidneys don't work well for a long time. Blood pressure (BP) is the force of blood against your blood vessels. Some people with CKD have trouble with their blood vessels not widening (vasodilation) or narrowing too much (vasoconstriction) during exercise. This research will look at these problems to find better treatments.

• **Who can participate?** Veterans with CKD Stages III and IV or those who received a kidney transplant, aged 18-75.
• **Study requirements:** Participants should exercise less than 20 minutes twice per week and be able to follow the study steps.
• **Exclusions:** People with severe CKD, certain heart or blood conditions, drug issues, or pregnancy cannot join.

Participants will help researchers find ways to improve exercise ability and blood pressure control in CKD patients. This study does not involve new treatments but focuses on understanding exercise-related problems. If you have CKD and meet the criteria, consider joining to contribute to important health discoveries.