Understanding the mecahnics of an erection might better help you understand the answer. An erection is limited by three things, the size of the tubes in your penis that hold the blood during an erection, the amount of blood that enters them and the amount of counter preseesure coming from the outside. A change in any of these will affect the size of your erection.
The size of the tubes is not going to change unless there is an injury, so that's not the problem. (It's also the reason why there is no possible way to increase the size of your penis).
As we get older it's natural for the amount of blood flow to decrease. This is due to a build up of plaque in the arteries leading to it as well as a weakening of the arterial walls. This is a perfeclt normal part of aging. It's also why when we're younger our erections point up at the ceiling and later they stick straight out. (This is called the erectile angle). If the decrease is severe enough there is an inability to get an erection (called Erectile Dysfunction) and medications such as Viagra or Cialis help to increase the flow.
That leaves us with counterpressure. As blood enters your penis it exerts an outward pressure. Surrounding air pressure pushes back and when the pressures equalize it can't grow any more. If you decrease the outside pressure more pressure can be exerted and it will grow bigger. (That's why you will have a larger penis at higher altitudes). Because of this penis pumps can increase your size temporarily. They create a vacuum around it allowing for an increase in penile pressure. This can help you get a larger erection but only for a minute or two. When you remove it the outside pressure will increase and they will equalize.
Not the answer you wanted to hear but those are the facts.
Copyright 1994-2018MedHelp.All rights reserved. MedHelp is a division of Vitals Consumer Services, LLC.
The Content on this Site is presented in a summary fashion, and is intended to be used for educational and entertainment purposes only. It is not intended to be and should not be interpreted as medical advice or a diagnosis of any health or fitness problem, condition or disease; or a recommendation for a specific test, doctor, care provider, procedure, treatment plan, product, or course of action. MedHelp is not a medical or healthcare provider and your use of this Site does not create a doctor / patient relationship. We disclaim all responsibility for the professional qualifications and licensing of, and services provided by, any physician or other health providers posting on or otherwise referred to on this Site and/or any Third Party Site. Never disregard the medical advice of your physician or health professional, or delay in seeking such advice, because of something you read on this Site. We offer this Site AS IS and without any warranties. By using this Site you agree to the following Terms and Conditions. If you think you may have a medical emergency, call your physician or 911 immediately.