Hi my name isXXXXX am an exercise physiologist and am here to assist.
So initially you need to clear with your physician to make sure you are otherwise fit for exercise. The physician (knowing your past history and condition)
will set your limits.
I noticed from your other question your doctor said " any reasonable exercise". Basically that means you are cleared for everything aside from extreme limit sports like triathlons, marathon running, powerlifting, and other impact sports. Regular weight training, cardiovascular exercise as well as any type of stretching activity is A-OK.
There is more though.
Generally speaking, provided the function of the kidney is good, you simply need to approach exercise as you would if you had 2 functional kidneys. Going 0 to 100mph the first day will set you up for injury but more importantly your kidney along needs time to adapt, just like all the rest
of the body systems. Easing into exercise, even for the healthiest of people is a strong recommendation. Doing too much too soon can be very discouraging because people get sore, tired, injured if they go nuts right off the bat.
You need to adjust your diet to not only benefit you as you exercise and provide proper nutrition and appropriate energy but also as a "forward thought" for your kidney as it will be doing the work of 2. Plenty of fluids throughout the day, complex carbohydrates, avoiding excess salts and sugars, lean proteins are a great way to round out the diet. Fruits and veggies should be pushed as well, very good source of nutrients.
Hydration, again regardless is going to be the same unless otherwise specified by the physician and its important to make sure you are consuming enough fluids as a majority of the body is made
of water but also requires it for a myriad of physiological processes.
So basically you need to be cleared by your GP, then you should start a general light mix. Flexibility(stretching), some gentle body weight exercises for the probable progression to weight training, and then a cardiovascular component to assist in general physical conditioning as well as the benefits to heart and cardiovascular system. As with anything, warming up, doing LESS than you think is "a good workout" and ending early is a good idea to make sure you are not "paying for it" the next day with soreness and other issues that come from that first day back to fitness.
A good walk, followed by some light stretching is the perfect, simple introduction.
If you need any other information simply let me know by hitting reply - please remember to provide a rating to our correspondence today as well.