What is a good starting point for resistance bike?

tonyaroseprewitt

I am 5'2 205lbs. I have been going to the gym for several months and I was doing really well. I lost about 30 lbs then in January was diagnosed with kidney cancer. I had one of my kidneys removed and six weeks later went back to the gym. I have been cleared to resume as before but the problem is I lost all of my stamina and strength I had gained so I am more or less starting over again. I have been going daily to the gym just walking on tread mill but can not pick my speed up past 3.2 mph due to a pain in one of my calfs. I have been trying to start on the reisistance bike but man about 1.5 miles is all I can handle. I am doing resistance of 5. Should I just stick with it and keep bumping it up little by little? I want to run so badly but the pain in my calf is preventing it so I want something else to help melt away the pounds.