Why do my balls move when I touch my thigh?

It’s common for men’s testicles to move around on their own throughout the day. But when you purposely touch or rub your thigh, it causes your testicles to move in a very noticeable way. What’s actually happening when you experience this strange phenomenon?

Table of Contents

Anatomy of the Scrotum

To understand why your testicles move when you touch your thigh, it helps to first understand what’s inside your scrotum. Your scrotum is the sac of skin that contains your testicles or testes. Inside each testis are tiny tubules that produce sperm cells. The scrotum has several important functions:

It keeps the testes at a temperature slightly cooler than normal body temperature. This helps with sperm production.
It protects the testes from trauma and injury.
It allows the testicles to freely move and adjust their position. This helps prevent torsion or twisting of the spermatic cord that provides blood flow to the testis.

The walls of the scrotum contain smooth muscle tissue that can relax or contract in response to signals from the autonomic nervous system. This allows the scrotum to pull the testicles closer to or farther from the body to maintain the ideal temperature.

Why Are My Testicles Constantly Moving?

If you pay close attention throughout the day, you’ll notice your testicles are in constant subtle motion. They naturally move up and down within the scrotum. This motion is controlled by the cremaster muscle surrounding the spermatic cord. When the cremaster muscle contracts, it pulls the testicle up toward the body. When it relaxes, the testicle descends farther from the body.

This frequent contraction and relaxation of the cremaster muscle causes the constant minor movement of the testes. It helps maintain optimal temperature to produce healthy sperm. The range of motion allows the testes to slightly shift position, preventing twisting or torsion of the spermatic cord.

Why Do My Testicles Move When I Touch My Thigh?

Touching or rubbing your thigh stimulates nerves that trigger a contraction of the cremaster muscle, which pulls the testicle up. Here’s a more in-depth explanation:

The skin on your thigh contains sensory receptors that detect touch, pressure, vibration, pain, and temperature.
Stimulating these receptors sends signals through sensory neurons to your spinal cord, and then up to your brain.

Your brain interprets the signals and recognizes you are touching your thigh.
In response, your brain sends signals back down your spinal cord and to your cremaster muscle, telling it to contract.
Contraction of the cremaster muscle causes your testicle to be pulled up toward your body in a swift motion.

This reflex helps protect the testicles from potential trauma or injury. If your thigh detects something unusual like rubbing or pressure, your scrotum reacts by pulling the testicles closer to the body and out of harm’s way.

Other Causes of Testicle Movement

There are other situations that can cause your testicles to move or draw up closer to your body:

Temperature changes – The cremaster muscle will contract in response to cold temperature to pull the testes closer and preserve heat.

Sexual arousal – During arousal, the cremaster muscle contracts to move the testicles closer to the body before relaxing to the elongated scrotal state.
Ejaculation – The testicles are drawn up tightly near ejaculation due to muscle contractions before relaxing afterward.
Injury – Any trauma to the groin area causes the cremaster muscle to contract to protect the testicles.

Medications – Certain drugs like antipsychotics, antiemetics, and narcotics can cause testicle contraction.
Medical conditions – Issues like a hernia, varicocoele, or infection can trigger spasms of the cremaster muscle.

When to See a Doctor

It’s normal for your testicles to draw up in response to rubbing your thigh. But in some cases, frequent or intense testicular movement can be a sign of an underlying problem:

Unusual pain, swelling, or redness of the scrotum or testicle
One testicle sitting higher than the other or retracting frequently
Trouble urinating or pain while urinating

Unexplained weight loss
Constant feeling of heaviness or fullness in the scrotum
Mass or lump felt on a testicle

See your doctor promptly if you have any of these symptoms along with frequent testicle movements. It may indicate an infection, hernia, varicocele, hydrocele, testicular torsion, or other medical issue needing treatment.

Is Constant Testicle Motion Normal?

It’s completely normal for your testicles to be in frequent subtle motion throughout the day. As long as it’s minor movement within the relaxed scrotum, there’s no cause for concern. The cremaster muscle automatically contracts and relaxes to gently shift your testicles and maintain the ideal temperature for sperm production.

More pronounced testicle retraction is also generally nothing to worry about when it’s triggered by something like rubbing your thigh, cold weather, sexual arousal, ejaculation, or anxiety. However, consistent testicle movements along with scrotal pain or other symptoms should be evaluated by your doctor.

Can I Prevent My Testicles From Moving?

You cannot completely prevent your testicles from moving. The minor shifting of your testes throughout the day is an automatic function controlled by your autonomic nervous system. However, you can take some steps to minimize excessive testicular motion:

Avoid rubbing or applying pressure to your thighs or genitals.
Wear loose, breathable underwear and pants to allow freedom of movement.

Maintain good posture while sitting and avoid crossing your legs.
Manage anxiety, stress, medications, or health issues contributing to testicle contractions.
Treat any skin disorders like jock itch that make the scrotum sensitive.

Apply warm compresses and take anti-inflammatories for temporary scrotal pain and swelling.
Perform Kegel exercises to strengthen pelvic floor muscles supporting the scrotum.

But keep in mind, normal cremaster muscle contractions that shift your testicles gently are not typically problematic. The movements help maintain proper temperature and prevent torsion. Completely immobilizing the testicles can actually impair fertility.

Takeaways

It’s normal for your testicles to frequently move subtly up and down within your scrotum throughout the day.
Touching or rubbing your thigh triggers a reflex that causes your cremaster muscle to suddenly contract and pull your testicle upward.
This response helps protect your testicles from potential injury or trauma to the groin area.

Other things that can make your testicles draw up closer to your body include temperature changes, sexual arousal, ejaculation, anxiety, medications, infections, and medical conditions.
Mild testicle motion is not concerning, but see your doctor if you have scrotal pain or swelling along with frequent contractions.

In conclusion, noticing your testicles move when you touch your thigh is common and not normally a cause for concern. The minor movements are a natural function of the cremaster muscle regulating temperature and preventing torsion of the spermatic cord. But pronounced or persistent testicle contractions along with other symptoms should be medically evaluated.

Cause	Mechanism	Management
Rubbing thigh	Touch receptors in thigh skin sense stimulation and trigger cremaster muscle contraction via spinal reflex	Avoid excessive rubbing of thighs
Temperature change	Cremaster muscle contracts in cold to preserve heat	Wear insulating underwear in cold weather
Sexual arousal	Autonomic pathways activate cremaster muscle	Normal response, no intervention needed
Ejaculation	Muscle contractions during ejaculation draw up testicles	Normal response, no intervention needed
Anxiety	Stress response activates cremaster muscle	Relaxation techniques, counseling, medications for anxiety
Medications	Side effects of some drugs stimulate cremaster contraction	Change medication if possible
Hernia	Protrusion of tissue can irritate cremaster muscle	Surgical hernia repair
Varicocele	Enlarged testicular veins put pressure on cremaster	Surgery or embolization to treat varicocele
Infection	Inflammation triggers muscle spasms	Antibiotics, anti-inflammatories

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