Effects of Combination Exercise on Fatigability in Veterans With Chronic Kidney Disease

This study tests whether a combination exercise program (aerobic exercise plus strength training) can reduce fatigue and improve physical function in veterans with moderate-to-severe chronic kidney disease (CKD stages 3 and 4) who are not yet on dialysis. People without kidney disease also participate as a comparison group. **You may be eligible if...** - You are 50 years of age or older - You can walk (with or without a walking aid) - You have chronic kidney disease stages 3 or 4 (kidney filtration rate between 15 and 59) - OR you are a healthy control without kidney disease (kidney filtration rate above 60) - You can speak and read English - You are oriented to person, place, and time **You may NOT be eligible if...** - You have had acute kidney injury in the past year - You cannot walk - You do not use the DC VA Medical Center as your main kidney care provider - You have uncontrolled heart disease, musculoskeletal disease, or joint pain that would prevent safe exercise - You plan to move away from the Washington, DC area within one year Talk to your doctor to see if this trial is right for you.