What is the Penis Made of?

October 24, 2023

4 mins

While about half of the population have one, most of us aren’t too sure what exactly it’s made of. What we do know about the penis is that it’s one of the main sources of sexual pleasure for men. 

The first time you became aroused as a young boy you may not have questioned the physiological process that was causing this new feeling. But maybe since then you’ve asked yourself about what’s going on down there. Lots of nicknames for the penis imply that it could be one thing or another, but these words create false ideas of what the penis is actually made up of.

We’re well aware that the penis is the primary sex organ in men, but what exactly is it?

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Is the Penis a Muscle or a Bone?

Contrary to popular belief, the penis is not a muscle. Instead, it’s made up of different components, each playing a crucial role in its function. While muscles are present in the pelvic region that help maintain an erection, they do not make up the structure of the penis itself.

Since the “love muscle” is actually not a muscle at all, people assume that it must be a bone. It’s not uncommon to believe as such, since erections are often called ‘boners.” 

But, let's set the record straight: the penis does not contain any bones whatsoever. It is primarily made up of spongy tissue – called the corpora cavernosa and the corpus spongiosum – that runs along the length of the penis. These tissues fill with blood during arousal, leading to an erection.

How Do Erections Work?

Although the penis is not a muscle, certain muscles are involved in the process of achieving and maintaining an erection. During sexual arousal, the brain signals the release of nitric oxide – which causes the muscles within the penis to relax – allowing blood to flow and engorge the organ, resulting in an erection.

The corpora cavernosa (or erectile tissue) is responsible for the majority of the penis's rigidity during an erection. It is composed of a network of blood vessels and smooth muscle, allowing it to expand and accommodate the increased blood flow. The corpus spongiosum surrounds the urethra and helps to maintain the shape and structure of the penis. 

 As these chambers become engorged with blood, the penis becomes erect.

To sustain an erection, the blood vessels that deliver blood to the penis remain dilated while the veins that usually carry blood away constrict. This helps to trap blood within the erectile tissue, maintaining the rigidity of the penis.

After ejaculation the body undergoes a refractory period. During this period, the penis gradually returns to its flaccid state. Hormonal signals cause the smooth muscles in the arteries and erectile tissue to constrict, reducing blood flow and allowing the erection to subside. 

Additionally, neurochemical changes and decreased arousal contribute to the return of the penis to its non-erect state.

What You Need to Know About Pelvic Muscles

The pelvic bones, also known as the hip bones or innominate bones, play a significant role in male sexual health. These sturdy, triangular bones form part of the pelvic region and have several important functions related to male reproductive and sexual well-being.

They provide support and protection for the pelvic organs, including the bladder, prostate gland, and reproductive organs like the testes and seminal vesicles. These bones contribute to structural stability during sexual activity, serving as attachment points for muscles involved in ejaculation and providing a firm base for movements. 

Additionally, the pelvic bones help regulate blood flow to the reproductive organs and penis, supporting erectile function and overall sexual health. They also house and protect the nerve pathways responsible for sexual sensation and response.

Try Kegel exercises

Kegel exercises are specifically designed to strengthen and tone the pelvic floor muscles. The pelvic floor muscles are a group of muscles that support the bladder, rectum, and sexual organs. Performing Kegels can be beneficial for both men and women in improving pelvic muscle strength and function.

To do Kegels, you'll need to identify the pelvic floor muscles first. You can do this by attempting to stop the flow of urine midstream or by imagining squeezing and lifting the muscles used to prevent passing gas. Once you've located these muscles, you can begin performing Kegel exercises.

Kegels involve contracting and relaxing the pelvic floor muscles repeatedly. Start by contracting the muscles and holding for a few seconds before releasing. Gradually increase the duration of the contractions over time. Aim for three sets of 10 repetitions per day, gradually working your way up to longer and more intense contractions.

How Rex MD Can Help

The misconception that the penis is a muscle persists, but it is not accurate. The penis is not a muscle or a bone, but rather a complex organ made up of erectile tissues, connective tissues, and blood vessels. 

While the penis is a stand-alone organ, the health of your many other organs can impact the health of your penis. So if your performance in the bedroom is of concern to you, talk to your doctor about possible factors that could be contributing to erectile dysfunction.

If you’re looking for other ways to enhance your sexual health, Rex MD helps men who want to improve their bedroom experience get ED meds. Answer a few questions, and a licensed health provider will determine if a medication like Viagra® or Cialis® could be right for you.