I am not making recommendations that what I did should be done by you. Each must follow their own doctors advice. I am just relating my experience.
In mid 2017 I had kidney removed. I immediately became classified stage 3b, with creatinine levels of 1.8 or 1.9. I followed all the advice. Diet. Drank 100oz of water daily. Briskly walked daily for 30 minutes or more. etc., etc. Over time I got occasional lower creatinine level of 1.7, if I was very hydrated before the test. In April I was diagnosed that the kidney cancer returned to my bones. I'm stage 4. No treatments available. Because of this I decided to forego all the normal efforts I was following for helping the remaining kidney. I had to have spinal surgery to repair cancer damage. Before the surgery tests showed my Creatinine had dropped to about 1.5. Big improvement. So for 4 to 6 weeks there has been no exercise. I only drink about 40 to 50 oz of water a day. I don't follow the CKD diet. I have not gone overboard and eat only bad things (beef, etc.,etc.). But I am eating a more normal diet without restrictions. I just had my blood and urine tests completed. When I went for the test I was not hydrated. It was an early morning appointment. MY CREATININE DROPPED DRAMATICALLY to 1.22!! MY BUN WAS 20!. Everything tested normal in urine except Potassium was 5.3 (the limit should be 1.2). Now either all my efforts from mid 2017 started to pay off, OR it makes me wonder about just following a "normal" diet for some reason is paying big dividends. I'm anxious to hear my kidney doctors opinion at the next appointment.