Why Does Getting Hit in the Testicles Hurt So Much?

pkripper503/iStock via Getty Images
pkripper503/iStock via Getty Images

More than any other bodily injury, getting hit in the testicles is probably what every man dreads most. Of all the soft, fleshy spots on the human body, none register the same kind of incapacitating, end-of-the-world pain as the family jewels.

What causes such inconceivable pain? Well, for starters, a shot to the balls is just like any other physical strike to the body: because of nerves, it’s gonna hurt. Unlike most other parts of your body, though, your scrotum lacks protection in the form of bones, large muscle mass, and fat. The testes are just wee little glands, and they’re going to absorb the whole force of the blow all on their own.

Another thing that makes a ball shot so painful is the same thing that makes almost every other sensation down there so much fun. Your groin has a ridiculously high number of sensory nerve endings, and such generous innervation makes good and bad touches alike very noticeable sensations.

And the pain doesn’t just stay down there in the scrotum. It insists on radiating throughout the groin and up into the abdomen (and, psychically, out to every other dude standing within a few feet), leading to a weird stomach ache. This is the work of a phenomenon known as referred pain, which is when a sensation originating at one spot travels along a nerve root to other parts of the body and is perceived as happening there, too. It’s the same thing that’s going when you get an ice cream headache. In this case, the pain starts in your balls and travels up the perineal and pudendal nerves and the spermatic plexus, which cover real estate in the groin and abdomen, around the spine and even a little ways down into the anus, to make it feel like death has come for most of your lower body.

Location, Location, Location

Why is such a sensitive and delicate body part just hanging there in the open? The placement of the testicles is inconvenient, but absolutely necessary. The testes’ job is to produce sperm, and sperm are very fragile. They’re extremely sensitive to high and low temperatures, and must be kept away from the rest of the body and relatively exposed to maintain the right climate. They can handle human body temps for only one to four hours, or the average amount of time it takes them to travel through the female reproductive tract and fertilize an egg. Internal testes or any type of significant shielding for them would heat them up too much, too early and make them drop out of the race well before reaching the egg, rendering them useless.

The scrotum isn’t just a dumb sack swaying in the breeze, though. In deference to our genetic interests, our bodies subconsciously thermoregulate our balls by flexing the cremasteric muscle and drawing the scrotum up closer to the body when it gets too cold and dropping it when it’s hot. This optimized, on-the-fly sperm storage is precise enough that each testicle can be repositioned independent of its twin in order to get the temperature just right, explaining their sometimes asymmetrical dangle.

10 Reusable Gifts for Your Eco-Friendliest Friend

Disposable tea bags can't compete with this pla-tea-pus and his friends.
Disposable tea bags can't compete with this pla-tea-pus and his friends.
DecorChic/Amazon

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By this point, your eco-friendly pal probably has a reusable water bottle that accompanies them everywhere and some sturdy grocery totes that keep their plastic-bag count below par. Here are 10 other sustainable gift ideas that’ll help them in their conservation efforts.

1. Reusable Produce Bags; $13

No more staticky plastic bags.Naturally Sensible/Amazon

The complimentary plastic produce bags in grocery stores aren’t great, but neither is having all your spherical fruits and vegetables roll pell-mell down the checkout conveyor belt. Enter the perfect alternative: mesh bags that are nylon, lightweight, and even machine-washable.

Buy it: Amazon

2. Animal Tea Infusers; $16

Nothing like afternoon tea with your tiny animal friends.DecorChic/Amazon

Saying goodbye to disposable tea bags calls for a quality tea diffuser, and there’s really no reason why it shouldn’t be shaped like an adorable animal. This “ParTEA Pack” includes a hippo, platypus, otter, cat, and owl, which can all hang over the edge of a glass or mug. (In other words, you won’t have to fish them out with your fingers or dirty a spoon when your loose leaf is done steeping.)

Buy it: Amazon

3. Rocketbook Smart Notebook; $25

Typing your notes on a tablet or laptop might save trees, but it doesn’t quite capture the feeling of writing on paper with a regular pen. The Rocketbook, on the other hand, does. After you’re finished filling a page with sketches, musings, or whatever else, you scan it into the Rocketbook app with your smartphone, wipe it clean with the microfiber cloth, and start again. This one also comes with a compatible pen, but any PILOT FriXion pens will do.

Buy it: Amazon

4. Food Huggers; $13

"I'm a hugger!"Food Huggers/Amazon

It’s hard to compete with the convenience of plastic wrap or tin foil when it comes to covering the exposed end of a piece of produce or an open tin can—and keeping those leftovers in food storage containers can take up valuable space in the fridge. This set of five silicone Food Huggers stretch to fit over a wide range of circular goods, from a lidless jar to half a lemon.

Buy it: Amazon

5. Swiffer Mop Pads; $15

For floors that'll shine like the top of the Chrysler Building.Turbo Microfiber/Amazon

Swiffers may be much less unwieldy than regular mops, but the disposable pads present a problem to anyone who likes to keep their trash output to a minimum. These machine-washable pads fasten to the bottom of any Swiffer WetJet, and the thick microfiber will trap dirt and dust instead of pushing it into corners. Each pad lasts for at least 100 uses, so you’d be saving your eco-friendly friend quite a bit of money, too.

Buy it: Amazon

6. SodaStream for Sparkling Water; $69

A fondness for fizzy over flat water doesn’t have to mean buying it bottled. Not only does the SodaStream let you make seltzer at home, but it’s also small enough that it won’t take up too much precious counter space. SodaStream also sells flavor drops to give your home-brewed beverage even more flair—this pack from Amazon ($25) includes mango, orange, raspberry, lemon, and lime.

Buy it: Amazon

7. Washable Lint Roller; $13

Roller dirty.iLifeTech/Amazon

There’s a good chance that anyone with a pet (or just an intense dislike for lint) has lint-rolled their way through countless sticky sheets. iLifeTech’s reusable roller boasts “the power of glue,” which doesn’t wear off even after you’ve washed it. Each one also comes with a 3-inch travel-sized version, so you can stay fuzz-free on the go.

Buy it: Amazon

8. Countertop Compost Bin; $23

Like a tiny Tin Man for your table.Epica/Amazon

Even if you keep a compost pile in your own backyard, it doesn’t make sense to dash outside every time you need to dump a food scrap. A countertop compost bin can come in handy, especially if it kills odors and blends in with your decor. This 1.3-gallon pail does both. It’s made of stainless steel—which matches just about everything—and contains an activated-charcoal filter that prevents rancid peels and juices from stinking up your kitchen.

Buy it: Amazon

9. Fabric-Softening Dryer Balls; $17

Also great for learning how to juggle without breaking anything.Smart Sheep

Nobody likes starchy, scratchy clothes, but some people might like blowing through bottles of fabric softener and boxes of dryer sheets even less. Smart Sheep is here to offer a solution: wool dryer balls. Not only do they last for more than 1000 loads, they also dry your laundry faster. And since they don’t contain any chemicals, fragrances, or synthetic materials, they’re a doubly great option for people with allergies and/or sensitive skin.

Buy it: Amazon

10. Rechargeable Batteries; $40

Say goodbye to loose batteries in your junk drawer.eneloop/Amazon

While plenty of devices are rechargeable themselves, others still require batteries to buzz, whir, and change the TV channel—so it’s good to have some rechargeable batteries on hand. In addition to AA batteries, AAA batteries, and a charger, this case from Panasonic comes with tiny canisters that function as C and D batteries when you slip the smaller batteries into them.

Buy it: Amazon

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30 Pungent Facts About Farts

This man is clearly not trying to hide the fact he just passed gas.
This man is clearly not trying to hide the fact he just passed gas.
BrilliantEye/iStock via Getty Images

Whether you openly admit it or desperately try to hide it, it’s an undeniable fact that every living and breathing human being farts. And while passing what you thought was going to be silent gas only to be wrong in certain situations can definitely be embarrassing, there’s something undeniably humorous about flatulence—no matter your age.

If you do love a good fart joke, you’re in good company. The very first recorded joke, which was written by the Sumerians and dates all the way back to 1900 BCE, was about—you guessed it—breaking wind. And some of the world's great thinkers, from William Shakespeare to J.D. Salinger, have slipped a fart joke (or 10) into their work.

In this episode of The List Show, we're sniffing out 30 fascinating facts about farts—from why humans expel gas to how often the average adult squeezes the cheese. You can watch the full episode below.

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