A man bike a ride

Does cycling affect sperm count? That question might sound like fear-mongering… until you find out there’s actual research behind it (spoiler!). 

This has sparked real debate, especially among active men who also want to become dads. Can your healthy habit be the thing holding you back from starting a family? That’s where things get interesting. Sounds like a contradiction, right? But the science around biking and fertility isn’t black and white.

Why Sperm Count Even Matters

Why sperm count matters?

Before going into what happens on the bike, it helps to understand the basics of male fertility. Here are the key factors:

  • Sperm count: how many sperm are present in semen
  • Motility: how well the sperm move
  • Morphology: their shape and structure

Even when just one of these is off, chances of conception may drop. That’s why figuring out whether cycling affect sperm count really does matter.

Cycling Affect Sperm Count: What Research Has Found

A Closer Look at the Concerns

One of the most widely cited studies comes from Boston University. It followed more than 2,200 men at fertility clinics and found something eye-opening: men who cycled for five or more hours a week were more likely to have low sperm counts and fewer moving sperm compared to those who didn’t ride much… or at all.

That seemed to suggest cycling affect sperm count when done intensely or for long periods.

Then came a broader analysis published in the American Journal of Men’s Health, which looked at multiple studies. It echoed the same idea: cycling, especially when intense or frequent, might lower sperm quality. Their advice? Men should “minimize scrotal heating.”

But Not Everyone Agrees

Here’s where it gets tricky. Another study, done in the UK and published in the Journal of Men’s Health, looked at more than 5,000 male cyclists and found no connection between biking and infertility. Even men who cycled more than eight hours per week didn’t show higher infertility rates.

In fact, those who cycled between four and six hours weekly (this considered as moderate) were less likely to report fertility problems.

So… what gives? Do both results cancel each other out? Not exactly. The key may be in the details: how long the rides are, what kind of gear is worn, or whether men already had fertility issues.

How Cycling Might Harm Sperm Health

Testicles infographic

Here are the primary ways cycling may interfere with sperm quality.

Scrotal Heat Buildup

Testicles produce healthy sperm at a temperature slightly cooler than the rest of the body. The ideal range is about 94°F to 96°F, or 34°C to 35.5°C.

Cycling for long periods can raise the temperature around the scrotum due to:

  • Tight-fitting clothing
  • Long sitting periods
  • Friction and movement

This heat can:

  • Disrupt sperm production
  • Damage DNA in sperm cells
  • Reduce sperm motility

If the goal is to increase sperm volume, managing testicular temperature becomes key. Wearing loose, breathable fabrics and taking breaks from the saddle can help.

Friction and Physical Impact

Constant pressure and motion against the saddle can cause:

  • Scrotal calculi (small hard deposits around the testes)
  • Testicular calcifications (linked to infertility)
  • Varicoceles (enlarged veins that reduce sperm production)

Hours on a hard saddle might cause more than just discomfort. One study looked at 85 healthy mountain bikers who rode at least two hours per day, six days per week. A shocking 94% had scrotal abnormalities like calcifications, cysts, and enlarged veins.

In comparison, non-cyclists had far fewer issues.

Reduced Blood Flow and Nerve Pressure

Extended time on a bicycle saddle can also lead to:

  • Genital numbness
  • Erectile dysfunction
  • Pudendal nerve entrapment

The perineum (area between the anus and scrotum) is sensitive. Prolonged compression here may reduce blood supply to the testicles. That impacts both sperm production and sexual function.

So if you're trying to increase sperm volume, circulation matters as much as count.

What About the Prostate?

The prostate plays a role in semen production. Some researchers have asked if long cycling might raise the risk of prostate issues.

A 2014 study found men over 50 who cycled more than 3.75 hours per week had a higher chance of prostate cancer. Other studies, though, didn’t find any clear link.

Still, since prostate health ties into semen quality, it’s another factor worth watching if the goal is to increase sperm volume and improve fertility outcomes.

How Much Is Too Much?

There’s no magic number, but researchers often point to around two hours a day as a threshold. Go beyond that regularly, and the risks may start to climb.

The American Heart Association recommends about 150 minutes of moderate activity per week, and cycling can absolutely be part of that. Just be smart about it. If fertility is a concern, cutting back a little might be a good idea.

So, does cycling affect sperm count in every man? No. But if you’re struggling to conceive and ride daily, it might be worth adjusting your routine.

Tips to Ride Without Risking Fertility

Want to keep riding and still protect sperm health? Here are practical steps that may help:

  • Use a padded or wider saddle
  • Try a noseless seat to ease perineal pressure
  • Choose looser, breathable shorts
  • Stand up frequently during long rides
  • Alternate biking with other workouts like walking or swimming
  • Avoid long, uninterrupted riding sessions  

What Else Affects Sperm Volume?

Cycling isn’t the only factor. If you're serious about trying to increase sperm volume, think about your full lifestyle. Things like stress, sleep, smoking, drinking, and even diet play a role.

Want some simple wins? Try these:

  • Eat foods rich in zinc and antioxidants.
  • Avoid processed meats, heavy alcohol use, and smoking.
  • Take supplements that support sperm production  like vitamin C, vitamin E, CoQ10, or tongkat ali  all of which may support sperm production.
  • Get enough sleep.

Final Thoughts

So… does cycling affect sperm count? The answer isn’t black and white. For most men, casual riding is likely just fine. But if you're clocking serious mileage every week (specially if you're trying to conceive) it’s worth considering a few changes.

There’s no need to ditch the bike completely. Just ride smarter, cooler, and with your future in mind. And if sperm health is already a concern, talk to a doctor.