Hi, hope you are well. To maintain your present muscle mass firstly maintain your exercise schedule. Do heavier weights with fewer reps. On the diet front get your sources of protein from milk,curd,sprouts, nuts and seeds. For
uric acid you do not need to cut out on all protein avoid alcohol esp. beer, lentils, peas, all of red meat,
liver and certain kinds of seafood. Have lots of fluids. Hope this helps.