How many times a week can I masturbate to remain fit and prevent impotence?
Well the frequency for One time masturbation should be 100 strokes atleast if you can keep up with that,and I know people who used to masturbate six times each day and now they are all married and have healthy children:)
Unless you are so obsessed with masturbation that it is causing you to ignore other parts of your life it really isn't a problem.
Heaven Answers "What is the ideal frequency of masturbating?"
If it feels good then its healthy.