Dear Doctor, i am 29 years old now and my penis length is 5′ when erected.

Patient: Dear Doctor, i am 29 years old now and my penis length is 5′ when erected. i heard too much about penis enlargement techniques such as , jelq and kegel exercises, can you advise me if this kind of exercises are really useful and medically proven as they been described? and if yes, is there any negative side effect for them or not on sexual health?thanks

Doctor: