Founder Essays

Aug 19, 2025

The Uncomfortable Truth About Bicycle Saddle Diseases

by James Parker, MD, co-founder of Cruzbike, Inc. Dr. Parker is a radiologist (a specialist in the imaging of human anatomy and disease conditions).

Introduction

If you’ve ever wondered if you’re doing permanent damage to your private parts when cycling, you’re not crazy. Your concerns are valid. As a physician and avid cyclist, I’ve seen firsthand how standard bicycle saddles harm riders. I’ve concluded that the best way to avoid Bicycle Saddle Diseases is to eliminate the saddle entirely; because for most of us, tweaking it—like adding cutouts—doesn’t fix the core issue.

The problem isn’t the saddle’s shape; it’s the body’s position atop it.

This paper explores bicycle saddle diseases (BSDs)- health risks tied to perineal trauma from standard bicycle saddles. I’ll detail these conditions, backed by science, and make the argument that saddle-free recumbent bikes make cycling available to a much larger subset of the population, not just the “resilient few” (a term I will define later). Another article will cover head, neck, and shoulder injuries from standard bikes’ high center-of-mass, head-forward stance. For now, let’s focus on what’s below the waist—and why, for most of us, the saddle must go.

What is a bicycle saddle disease?

Bicycle saddle diseases (BSDs) are chronic or acute injuries or illnesses caused by the accumulation of pressure and trauma to the perineum directly related to the use of a bicycle saddle.

For men, bicycle saddle diseases include:

erectile dysfunction
urethral strictures
infertility
prostatitis
prostate cancer.

For women, bicycle saddle diseases include:

vulvar numbness
vulvar pain
labial fibrosis
Urinary Tract Infections (UTIs)

Both men and women are subject to perineal folliculitis and furuncles (saddle sores, the most common BSD); and to arterial endofibrosis.

If you are interested in riding a road bike, you owe it to yourself to read and understand this material.

Cycling has wonderful cardiovascular and mental health benefits, but those shouldn't come, and don't have to come, with the risk of a bicycle saddle disease.

The problem with bicycle saddles

A large portion of the rider’s weight is placed on the bicycle saddle, compressing important structures in the soft fleshy part of the pelvis called the perineum. In men, the parts compressed include the prostate, urethra, and the pudendal nerves and arteries supplying the penis. In women, the saddle may cause vulvar trauma and compression of the pudendal arteries and nerves supplying the vagina and clitoris, with resulting genital numbness, pain, labial fibrosis, and subcutaneous perineal nodules. The saddle does not just compress, but also causes friction and repetitive trauma, as anyone who has ridden over rough roads or hit an unexpected pothole knows.

The heavier you are, the more pressure is exerted on the perineum when you sit on a saddle. Pressure is defined as the force per unit area. The heavier the rider, the more weight (force) is applied to the perineum. The smaller the surface area of the saddle, the higher the pressure for any given weight. Saddles with cutout designs actually produce higher peak pressure on the perineum because the surface area is smaller. A University of North Carolina study showed “ergonomic” saddles failed to prevent penile blood flow drops in men aged 20-50 [1].

Don't be squeamish. Study the images below carefully if you want to understand why the saddle should go the way of the lawn dart.

First is an image of the male perineum seen from below with the skin peeled away to reveal the delicate arteries and nerves, with an overlay of a bicycle saddle (in gray) with a "cutout" which is supposed to lessen compression. The cutout may actually make compression on certain nerves worse by forming edges with higher pressure. Take note of the thin branching yellow structures. Those are the nerves that may die from repeated trauma and ischemia.

an image of the male perineum seen from below with the skin peeled away to reveal the delicate arteries and nerves, with the outline of a saddle (in green) with a "cutout" which is supposed to lessen compression. The cutout may actually make compression on certain nerves worse by forming edges with higher pressure. Take note of the thin branching yellow structures. Those are the nerves that may die from repeated trauma and ischemia.

Below, the MRI image on the left shows what the vessels in the perineum, near the base of the penis, normally look like (the green arrows are pointing to the vessels, which appear as white circles and ovals). Now look at those vessels on the right (red arrows). They are compressed (flattened) by the saddle.[1] You can't see the nerves on the MRI because they are too small, but they run next to the arteries and veins. Every second that a cyclist spends on a bicycle saddle is time spent compressing vital nerves and blood vessels that supply the sex organs.

An MRI image. On the left shows what the vessels in the perineum, near the base of the penis, normally look like (the green arrows are pointing to the vessels, which appear as white circles and ovals). Now look at those vessels on the right (red arrows). They are compressed (flattened) by the saddle.1 You can't see the nerves on the MRI because they are too small, but they run next to the arteries and veins. Every second that you spend sitting on a bicycle saddle, you are compressing vital nerves and blood vessels that supply your sex organs.

The MRI shows how the vessels are physically compressed by the saddle. Also note that the thick layer of fat between the saddle and the penile vessels does not prevent the compression because the pressure is simply transmitted through the fat. This explains why padded shorts, which may reduce friction to the skin, do not prevent compression of the vessels and nerves supplying the genitals in men or women.

A different study measuring oxygen levels in the penis found a remarkable 70% drop after just a few minutes on the saddle. It’s also important to note that this does NOT happen when riding on a recumbent bicycle [2]. Hypoxia and ischemia to the penis is a problem limited to standard bicycles, when riding in either an upright or aerodynamic tucked position.

Graph showing results of study A different study measuring oxygen levels in the penis found a remarkable 70% drop after just a few minutes on the saddle. It’s also important to note that this does NOT happen when riding on a recumbent bicycle [2]

Understanding Sampling Bias

Someone reading this may get upset and use Google or ChatGPT to find a study that says cycling does not cause, for example, erectile dysfunction (ED). They may find a study such as the 2020 study: Cycling and men’s health: A worldwide survey in association with the Global Cycling Network. The problem with this study, and many others like it, is called "sampling bias" which is a type of selection bias.

A cartoon illustrating Sampling Bias. It says, We received 500 survey responses and found that people love responding to surveys."

Here’s how studies sponsored by the cycling industry work: they survey existing cyclists that they find through cycling clubs, subscribers to cycling magazines, or followers of cycling social media channels. The ask those riders if they have erectile dysfunction (ED). When the results are tallied up, they often find that the survey respondents rate of ED is no higher than non-cyclists. This selection bias may apply to many of the other bicycle saddle diseases (BSDs), not just ED.

To understand selection bias, let's go through a thought experiment.

Understanding Sampling Bias: The Kayak-Migraine Thought Experiment

Migraines affect between 10% and 15% of the adult population in the United States. Now imagine for a moment that kayaking caused a severe migraine in 70% of the adult population (of course it does not but just pretend for now that it does). Also pretend that this kayaking-migraine correlation is widely known.

Now imagine that you are an individual who gets a debilitating migraine every time you go kayaking. Do you think that you would join a kayaking club, subscribe to a kayaking magazine, or follow a YouTube kayaking channel? Of course not! You would find some other recreational activity with which to occupy your time.
Now imagine if the kayak industry surveyed kayak club members, common sense tells us that they would find close to NONE of the survey respondents would report a migraine headache after kayaking, even though we know (for the purpose of this thought experiment) that kayaking causes a migraine in 70% of the general population. This kayak-industry “research” might even find that migraine headaches were significantly LESS common in kayakers when compared to the general population, and these results might encourage some kayaking enthusiasts to claim that kayaking PREVENTS migraines… even though we know that the opposite is true. This is essentially how the cycling industry gaslights people into thinking that cycling on a standard bike is actually quite healthy.

Understanding Sampling Bias: The Real-World Peanut Festival Scenario

Here's a final example of selection bias using a real-world scenario. Approximately 1.5% of the population is allergic to peanuts; if they eat a peanut or breathe peanut dust, they may become very ill or die.
Approximately 200,000 people visit the annual National Peanut Festival in Dothan, Alabama, which features every variety of peanut product imaginable. If peanut festival visitors were a random sample of the population, we would expect about 3,000 allergic reactions to occur each year at the Dothan festival.
But that’s not what happens. There are few or no serious allergic reactions because people with serious peanut allergies don’t go to peanut festivals.

What if the peanut industry surveyed attendees at the peanut festival and determined that peanut consumption is safe for everyone? They would be denounced as unethical and irresponsible.

Many cyclists blithely accept cycling industry sponsored survey studies because they do not understand selection bias and they don’t want to believe that the activity they love could be causing permanent injuries.

For the most part, survey studies on ED and cycling should be disregarded. They do not refute strong evidence that cycling causes erectile dysfunction and other BSDs.

Who are the resilient few?

I believe, based on reading scores of articles about BSDs, that there is a subset of men and women (about 20-30% of the population) who are endowed with anatomy that is protective of the delicate arteries and nerves in the perineum. Perhaps their nerves run inside a protective bony groove or they have an extra layer of protective fascia. These are the hardy people who lead cycling clubs, compete in amateur and professional bicycle races, and swear that they never have ED or genital pain. I call them the “Resilient-Few”. They are also the ones who fiercely defend their chosen sport on social media and are most likely to respond to surveys about erectile dysfunction. For the rest of us “normal” people who lack their special anatomy, padded shorts, saddles designed with cutouts, and proper-bike-fit are not enough to overcome the fact that our perineums were not built to support our body weight.

If you are a member of the Resilient-Few, congratulations. Keep reading and see what may happen to the rest of us who aren’t as fortunate.

Bicycle Saddle Diseases: Erectile dysfunction

Erectile dysfunction (ED) may have a devastating effect on a man's quality of life. But how do we know that cycling causes ED? The proper scientific method to determine if cycling causes ED would be to perform a randomized controlled trial where a random selection of men are randomly assigned either to bicycle regularly or do another activity (e.g. jogging) and then after a designated period of time, the ED rates before and after exposure to these activities are compared. As simple as this would be to conduct, it has never been done. We all learned in high school that correlation of two observed phenomenon does not mean one causes the other. For example, ice cream consumption and shark attacks are well correlated, but eating ice cream does not cause shark attacks. The shark-attack-ice-cream correlation is related to the confounding variable of warm weather.

Then, how do we determine if a relationship (e.g. cycling and ED) is mere correlation, or causal?

In 1965, Sir Austin Bradford Hill proposed nine criteria to help determine if one thing causes another.

The Bradford Hill Criteria are:

Strength of Association: A strong association (e.g., a high relative risk or odds ratio) is more likely to be causal than a weak association, as strong effects are less likely to be explained by bias or confounding.
Consistency: The association is observed consistently across different studies, populations, and circumstances. Replicability strengthens the case for causation.
Specificity: Causality is more likely if a specific exposure is associated with a specific outcome rather than multiple outcomes.
Temporality: The exposure must precede the outcome. This is the only criterion that is universally considered essential for establishing causality.
Biological Gradient: A dose-response relationship supports causation; as the dose of exposure increases, the risk of the outcome also increases.
Plausibility: The association should be biologically plausible, based on existing knowledge of mechanisms or theories.
Coherence: The association should not conflict with the current understanding of the natural history and biology of the disease.
Experiment: Evidence from experiments, such as controlled studies or interventions, strengthens the argument for causality.
Analogy: If a similar relationship has been demonstrated with another exposure-outcome pair, it supports causation (e.g., the similarity between smoking and lung cancer compared to second-hand smoke exposure and lung cancer).

Now let's apply The Bradford Hill Criteria to what we know about cycling and erectile dysfunction:

1. Strength of Association

A 2021 meta-analysis involving a systematic review of 843 studies examining cycling as a cause for ED found an odds ratio of 2.00 after controlling for age and comorbidities.[4] That's a 200% increased risk of getting ED if you are a cyclist. That's a strong association.

2. Consistency

The association of ED and bicycle saddles has been reported in hundreds of articles for many decades. If we consider horse saddles (which also place at least some of the rider’s weight on the perineum), we can extend that to millennia. Hippocrates, the father of modern medicine, observed that horseback-riding caused ED. He said the following about men who spent a lot of time in the saddle: "the constant jolting on their horses unfits them for intercourse."[5] That was 2500 years ago. That's consistency.

3 , 4, and 5. Specificity, temporality, and dose-response

Specificity measures whether an exposure is linked to a specific outcome, rather than a wide variety of unrelated effects. In this case, ED is not the only outcome. As we will explore later, other outcomes, such as prostate cancer and urethral strictures, are linked to the bicycle saddle through similar mechanisms. Many causal relationships lack specificity (e.g., smoking and multiple diseases), so low specificity doesn’t negate causality, especially when the other conditions are plausibly related to the same injury.

Temporality measures the relationship between exposure and outcome over time. Many studies note that the ED occurs immediately AFTER the cycling exposure, and that longer rides (higher dose) are associated more strongly with ED.

Dose-response (biological gradient) is probably the most important of all the criteria. If larger/longer exposures are more frequently linked to the outcome, then the relationship is most likely causal, not just correlation. We clearly see this in the studies on cycling and ED.

6, 7, and 8. Plausibility, Coherence, and Experiment

A clear "yes" to all of these. Just look at the anatomy relative to the saddle in the above images. Compression, repetitive trauma, and ischemia (decreased blood flow) are all known causes of permanent tissue damage and loss of function. Laboratory experiments with oxygen sensors confirm a rapid and dramatic drop in perfusion of the penis when sitting on a bicycle saddle.[2] In a 2002 study of police officers assigned to bicycle patrol duty, 91% complained of genital numbness, and they had significantly fewer nocturnal erections than officers not assigned to bicycle duty.[7] This study is especially important because it does not have an obvious selection bias. The subjects are random patrol officers, not self-selected cycling enthusiasts.

9. Analogy

Workers who use a jackhammer may get hand-arm vibration syndrome (HAVS). HAVS may cause loss of dexterity and permanently damage the nerves, blood vessels, and muscles in the hands and arms.

After applying the Bradford Hill Criteria, we can say without a doubt that cycling a lot may cause ED, with at least a 200% increased risk compared to non-cyclists. I say “at least” because even the studies that show a strong correlation between cycling and ED are affected by sampling bias, which would tend to grossly underestimate the true relative risk.

Bicycle Saddle Diseases: Prostatitis and Prostate Cancer

The same repetitive injury and ischemia that causes ED may also cause prostatitis (inflammation of the prostate) and prostate cancer.

First, let's take a look at the location of the prostate relative to the bicycle saddle, and see if injury to the prostate is plausible.

The prostate and urethra sit in the middle of the perineum, just above the center of the bicycle saddle. It is not surprising that saddle pressure and shocks are going to be transmitted to the prostate, where they may cause inflammation.

Bicycle Saddle Diseases: Prostatitis and Prostate Cancer

Studies have shown a temporary rise in serum PSA levels following cycling, particularly in men over age 50.[7-11]

If you find a study online that says cycling does not cause an increase in PSA, read the whole article in detail, because they are probably testing young men. Why is this important? PSA is a protein found in the prostate that may be released when the prostate is infected, inflamed, or has cancer. Some studies have examined "regular" cyclists and not found an increase in PSA after they go cycling. These studies suffer from the same selection bias as the studies that say cycling does not cause erectile dysfunction.

"Regular" cyclists are not necessarily like the rest of us. Until someone conducts a properly designed randomized controlled study, we will have to approach the question keeping in mind the Bradford Hill Criteria for causation.

Applying the Bradford Hill Criteria to what we know about cycling and prostatitis and prostate cancer:

Strength of Association

The best study on the subject found that cycling more than a few hours per week is strongly associated with an increased risk of prostate cancer in men over 50. These results were published in the Journal of Men’s Health in 2014. The name of the study: An observational study of erectile dysfunction, infertility, and prostate cancer in regular cyclists: Cycling for Health UK; which I will call the CHUK study for short. In this study funded by the cycling industry (Cycling Weekly magazine, Cycling Fitness magazine, CTC, British Cycling, and Sky Ride) over 5000 male cyclists completed a survey about their health and cycling habits.[12]
The 2000+ men over 50 were divided into four groups based on how many hours per week they rode their bike.

Group and # of Men	Cycling Hours Per Week	Cycling Minutes Per Day	Relative Risk of Prostate Cancer*
I (511)	0 to 3.75	0 to 32	1.0 (the control group)
II (449)	3.75 - 5.75	33 to 49	2.94
III (569)	5.76 - 8.5	50 to 73	2.89
IV (498)	>8.5	over 73	6.14

*adjusted for age, smoking, body mass index, hypertension, alcohol intake, and other physical activities

They found that men over 50 who cycle between 3.75 and 8.5 hours per week (Group II and III in the above table) have a 2.9x (290%) increased rate of prostate cancer compared to the cyclists who ride less than 3.75 hours per week; and that is after controlling for confounding variables such as age, BMI, blood pressure, etc. If a nearly a 3-fold odds ratio does not get your attention, then look at the relative risk of prostate cancer in the men over 50 who cycle more than 8.5 hours per week (group IV). Their relative risk of prostate cancer jumped to 6.1x (a 610% increase).

That’s a clear dose-response, which is strong Bradford Hill evidence for a causal relationship between the exposure (cycling) and the outcome (prostate cancer). Why would the CHUK study reveal a strong association between cycling and prostate cancer, but not cycling and ED? Because prostate cancer develops slowly, silently, and without any symptoms. Even the resilient few who seem to be immune to the ED complications of cycling are not immune to the increased risk of prostate cancer.

Coherence: Does the association of cycling and prostate cancer match our current understanding of the natural history and biology of the disease?

Yes. It is widely known that chronic injury and the associated inflammation can potentially contribute to the development of cancer. This connection is based on biological mechanisms where persistent injury or irritation leads to a chronic inflammatory state, which in turn creates an environment conducive to cancer development. Here's how this process might work.

Repeated tissue damage from injury can lead to ongoing inflammation. Chronic inflammation involves the release of inflammatory cytokines, growth factors, and reactive oxygen species (ROS), which can cause DNA damage and promote cellular mutations. To repair injured tissue, the body induces increased cellular proliferation. With more frequent cell division, there is a higher chance of mutations and, eventually, cancer. Persistent injury also results in fibrosis (scar formation), altering the tissue microenvironment. These changes can disrupt normal cellular signaling and promote a tumorigenic environment. And finally, chronic injury can lead to epigenetic modifications, such as DNA methylation and histone modification, which may silence tumor suppressor genes or activate oncogenes (references 13-18).

Analogy: Examples of other cancers linked to chronic injury

Esophageal Cancer: Chronic injury from gastroesophageal reflux disease (GERD) can lead to Barrett's esophagus, a precursor to esophageal adenocarcinoma.
Liver Cancer: Repeated liver injury due to hepatitis or chronic alcohol use can cause cirrhosis, which increases the risk of hepatocellular carcinoma.
Skin Cancer: Chronic exposure to ultraviolet radiation causes repeated skin injury, leading to mutations that may result in melanoma or squamous cell carcinoma.
Bladder Cancer: Persistent irritation from schistosomiasis infection or chronic catheter use has been associated with an increased risk of bladder cancer.

How did the cycling world respond to the 2014 CHUK study? What is the counter-argument against cycling causing prostate cancer?

The CHUK study's implication that cycling may cause prostate cancer made headlines and shocked cyclists around the world. Rather than prompting a well-funded randomized controlled trial, the cycling industry responded with... another gaslighting survey study, this time sampling cyclists who follow the Global Cycling Network (GCN) on YouTube.

The respondents to the GCN survey were much younger than the CHUK study, which is not surprising since the YouTube audience is famously young.

Also not surprisingly, the GCN study, published in 2020, found no association with cycling and prostate cancer.

However, a detailed reading of the article (not just the abstract or the YouTube summary) shows that only 9% of the subjects in the study were over the age of 54 (only 726 men, compared to over 2000 men over 50 in the CHUK study).

Moreover, there were spurious results in the older men in the GCN survey, with men in the 54-64 year age group reporting BETTER urinary voiding scores than younger men in the 35-44 and the 45-54 year age groups. The line in the chart below should be straight or mildly curved; certainly not a line with a big hitch in it. This is a red flag that the data is untrustworthy.

In summary, the GCN study (flawed by sampling bias, too young a study population, and dubious data) does nothing to refute the evidence that cycling causes prostate cancer in men over age 50.

But I read that cycling reduces the risk of prostate cancer?

Improving your level of fitness and having a healthy (not obese) BMI lowers your risk of prostate cancer and many other cancers.[18-23] The percentage by which improved fitness lowers the risk of prostate cancer varies based on the intensity, type, and duration of physical activity, as well as individual factors such as age, genetics, and overall health.

But the effects are moderate, in the range of a 10 to 40% reduction in prostate cancer risk. A meta-analysis by Friedenreich et al. (2016) showed a 19% lower risk of advanced prostate cancer in men who were physically active.

In a 2011 study (Kenfield et al) men doing more vigorous running or cycling had a 30–40% lower risk of advanced or fatal prostate cancer.

But remember that the CHUK study found an almost 300% increase in prostate cancer in men who cycled more than 33 minutes/day and a 600% increase in men who cycled more than 73 minutes/day, compared to men who cycled less than 33 min/day.

Therefore, there is a strong net increase in prostate cancer risk in men over 50 who are doing a lot of hours on the saddle each week, despite the overall health benefits.

Also keep in mind that those hours on the saddle aren't always done on the road. Indoor cycling (e.g. Zwift and Peleton) are popular activities that also compress the perineum and may cause BSDs. These hours on the saddle should also be switched to the recumbent cycling position.

Bicycle Saddle Diseases: Urethral Strictures

I know a urologist who says he commonly sees urethral strictures in his male cycling patients. A urethral stricture is an area of partial blockage in the tube that carries urine from the bladder to the end of the penis. Strictures may occur from years of chronic injury, or from one sudden accident where the perineum slams into the saddle, which may occur, for example, if the chain breaks at just the moment the rider is standing on the pedal trying to get started after a stop. Looking closely at the image below, it is obvious why the urethra gets injured by the saddle. It sits just above it, with very little protection. Urethral strictures can impact your quality of life, slow down your urinary stream, and have other genitourinary symptoms. Sometimes they require surgery or stent placement.

A 2018 study published in the Journal of Urology reported that cyclists were 2.5x (250%) more likely to have urethral strictures compared to swimmers and runners.[24] I believe that the increased risk of urethral structure from cycling is actually much higher than 250%, due to the effects of selection bias, which we have discussed previously.

Bicycle Saddle Diseases: Arterial Endofibrosis

Too much riding in the aero-tuck position (leaning forward so that the upper body is parallel to the ground) on a standard bike saddle may damage large arteries in the pelvis in a disease process called arterial endofibrosis.

The human body was not designed for prolonged exertion of the lower extremities while the hips are severely flexed.

This position may cause a fold or kink in the external iliac artery, with resulting endofibrosis (thickening and scar formation of the inner wall of the artery).

This typically presents with pain, cramping, or fatigue in the thigh or calf muscles during or after an intense workout. It may also result in numbness or tingling in the leg or foot; or coolness or discoloration during or after exercise. If symptoms are ignored and the damage continues, this may result in permanent arterial narrowing and may require surgical intervention (Ref 24-31).

Humans evolved to produce maximal power while walking or running with the hips reaching full extension, a position much more closely approximated when cycling in the recumbent position or when standing up out-of-the-saddle on a standard bike.

Bicycle Saddle Diseases: Infertility, Low Sperm Quality

A study presented at the European Society of Human Reproduction and Embryology's annual conference in 2009 found that triathletes engaging in extensive cycling training had poorer sperm morphology, to the point of risking their fertility.

The more time spent cycling, both in duration and distance, the greater the decline in sperm quality.[32]

This decline in sperm quality did not correlate with more running or swimming training, but only with cycling.

This may not be an issue for older cyclists, or recreational cyclists, but it is another BSD that may be important if you want to cycle a lot and be fertile.

Bicycle Saddle Diseases: Vulvar pain, numbness, female sexual dysfunction, and UTIs

As bad as the men have it, BSDs in women may be worse. Take a look at where the saddle is rubbing and applying pressure on the female perineum. It’s basically the entire vulva, including the clitoris, urethral opening, labia minor, labia majora, and vaginal introitus. There are delicate nerves, arteries, and veins supplying the vulva that are subject to severe compression and damage. The next image shows a cut-away model-view of the female perineum viewed from below, with a saddle with a cutout superimposed.

Bicycle Saddle Diseases: Vulvar pain, numbness, and female sexual dysfunction

In the illustration above, note that the urethra sits between the clitoris and the vagina. Prolonged pressure on the urethra can drive bacteria up the urethra, triggering a urinary tract infection (UTI). Padded shorts, which block ventilation and trap heat and moisture may increase bacterial levels and contribute to the risk of UTIs [36, 39-43].

Regarding sexual dysfunction and genital numbness, it's important to understand that no two people have the exact same network of nerves and arteries supplying their genitals. The pattern is as unique as a fingerprint. This is why a specially designed saddle with cutouts may help one person, but actually make the problem worse for someone else.

Bicycle Saddle Diseases: Labial Fibrosis

The next image shows what labial fibrosis and furunculosis may look like when they develop from extensive riding on a standard bicycle. Fibrosis can make the labia hard, bumpy, and painful, sometimes requiring surgical labiectomy in female cyclists.

Studies have found high rates of vulvar pain, vulvar numbness, and sexual dysfunction in surveyed female cyclists. In one survey of female cyclists (average age 48 years), 69% reported genital pain, 58% reported genital numbness, and 54% reported sexual dysfunction. And don’t forget the effects of selection bias. If 69% of female cyclists report genital pain, we can assume the percentage of non-cyclist women who would experience genital pain if they took up cycling would be much higher.

Bicycle Saddle Diseases: Labial fibrosis

If you want to read more stories about female BSDs, the Bicycling article: "Cycling’s Silent Epidemic" by Gloria Liu, published in 2024. Liu does a good job describing the problem, documenting numerous women with lopsided, painful, and swollen labia from too much time on the bike saddle. But rather than address the root cause (the labia are not designed to be a weight-bearing structure), she promotes de-stigmatizing labiaplasty (surgery to cut away parts of the labia) for female cyclists, and tweaking the saddle (making it wider here, narrower there, etc.).

While there are some female cyclists who will benefit from a different saddle, it’s worth repeating that the main problem is not the shape of the saddle but rather the position of the rider's vulva above it.

The most effective solution is also much easier. Ride a recumbent and get the pressure and friction off of the vulva. For more information on women’s BSDs, read Liu’s article and review references 33-43.

The Solution: a Healthier, Thrilling Way to Ride

Now you know you are right to be concerned about the health risks from standard bicycle saddles. Avoiding prolonged contact with standard saddles is wise if you want to reduce your risk of pain, injury, and illness. Studies show that saddle pressure can reduce penile blood flow by up to 70% in just a few minutes, increase prostate cancer risk by 2.9–6.1 times in men over 50 who cycle heavily, and cause genital pain or numbness in 69% of female cyclists [References 1a, 12, 36].

These aren’t mere discomforts or minor irritations of the private parts; they’re real threats to your health, quality of life, sexual wellness, and longevity.

But there’s a game-changing solution: recumbent bicycles like those from Cruzbike. By shifting to a laid-back riding position, Cruzbike recumbents eliminate perineal pressure entirely, protecting your vital nerves and arteries. For female cyclists, recumbents place the vulva in a forward-facing, non-weight-bearing position, where ventilation is improved and thick padded shorts aren't needed, thus reducing the risk of a UTI, genital pain/numbness, and labial fibrosis.

For male cyclists, recumbents don't crush the nerves and arteries that allow you to maintain an erection. That's a really big deal for most guys. But so is reducing your risk of urethral strictures, prostatitis, and prostate cancer.

Imagine cycling without the ache of saddle sores or the worry of long-term damage—just pure, exhilarating freedom. Our bikes, the V20c, S40, Q45, and T50, are designed for speed, comfort, and performance, whether you’re tearing through a 200-mile ultracycling race, hauling gear on a cross-continent adventure or just cruising for fun around town.

The front-wheel-drive system offers unmatched efficiency, letting you climb powerfully up hills, and then leave the traditional bike riders behind on the flats and downhills… all while enjoying a clear view of the road and a relaxed posture that spares your neck, shoulders, wrists, and genitals.

My wife, Maria, and I have logged 100,000 miles on these bikes, from mountain races to time-trials to leisurely tours; and our customers have racked up millions more worldwide. They’ve discovered what we have—a cycling experience that’s not just healthier but downright thrilling.

Your concerns about saddle-related health risks are valid. Don’t let them stop you from enjoying cycling’s incredible benefits.

We invite you to experience Cruzbike for yourself. Visit cruzbike.com to explore our models, find a test ride near you, or connect with our community of riders who’ve made the switch. Whether you’re a weekend warrior, a fitness enthusiast, or dreaming of your next big race, Cruzbike opens the door to a new kind of cycling adventure—one that’s safe, comfortable, and undeniably badass. Come ride with us and feel the difference!

REFERENCES:

In order to make this article easier to read, I placed citations numbers bracketed in the text for only the more important references. Those are listed below, as well as other references if you want to read more deeply into any of these topics.

1a. Cohen, J. D., & Gross, M. T. (2005). Effect of bicycle racing saddle design on transcutaneous penile oxygen pressure.Journal of Sports Medicine and Physical Fitness, 45(4), 409-418.

Bressel, E., Reeve, T., Parker, D., & Cronin, J. (2007). Influence of bicycle seat pressure on compression of the perineum: A MRI analysis. Journal of Biomechanics, 40(1), 198–202. https://doi.org/10.1016/j.jbiomech.2005.11.017

Sommer, F., Schwarzer, U., Klotz, T., Caspers, H. P., Haupt, G., & Engelmann, U. (2001). Erectile dysfunction in cyclists: Is there any difference in penile blood flow during cycling in an upright versus a reclining position? European Urology, 39, 720–723.

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