Effects of an Aerobic Exercise Program on Cardiovascular Risk in Patients With Chronic Kidney Disease or Rheumatoid Arthritis

This study is testing whether a structured aerobic exercise program can reduce cardiovascular (heart and blood vessel) risk in people living with chronic kidney disease (CKD) or rheumatoid arthritis (RA) — two conditions that significantly raise the risk of heart problems. **You may be eligible if...** - You have been diagnosed with chronic kidney disease (stage 3 or 4, not on dialysis) or rheumatoid arthritis with active disease - You have a medical certificate confirming you can safely do physical exercise - You are enrolled in a French social security health scheme **You may NOT be eligible if...** - You are on unstabilized steroid therapy or taking more than 10 mg of prednisone per day - You have uncontrolled high blood pressure - You are pregnant - You have a condition (neurological, cardiovascular, respiratory, or musculoskeletal) that prevents you from exercising - You are unable to understand or follow an exercise program - You do not have health insurance - You are currently enrolled in another study that could affect your heart or inflammation levels Talk to your doctor to see if this trial is right for you.