The answer to this question is Proteinuria. The Proteinuria is a situation where in thr urine have excessive amount of protein. Having proteinuria is a sign that a person has a kidney disease / damage. The factors that can cause proteinuria is having diabetes and a high blood pressure.
I would tell him that his health problems are completely confidential and that I would not tell his wife. If the wife asked me, I would say to talk to your husband he will explain everything.
Use the settings of the machine to decrease the intensity George can work out for the same amount of time but with a lower intensity that way his heart rate won't increase