By the time she finished her first century ride, my friend Sarah had already made a decision: she would never do that again. It wasn't the distance. It wasn't the climbing. It was the searing, persistent numbness that settled into her pelvic region around mile sixty and refused to leave until three days later. Her bike fit was professional. Her shorts were high-end. Her saddle? It was marketed specifically to women—shorter, wider, with a generous cut-out. And it still failed her.
Sarah's experience is not unusual. It is, in fact, the norm for a staggering number of female cyclists. And it points to a deeper problem that the cycling industry is only now beginning to address: the bicycle saddle was never designed for the female body.
The Shape We Inherited
Let's travel back to the late 1800s, when the bicycle was transforming personal transportation. The saddles of that era were narrow, long, and hard—perfect for men in wool trousers riding on smooth roads. Women, when they cycled at all, often rode side-saddle or on modified frames that didn't require a traditional saddle.
When women's cycling finally gained acceptance in the early twentieth century, the saddles they rode were essentially men's saddles made slightly smaller. The assumption was simple: a woman is a smaller man, so a smaller saddle will fit. This assumption persisted for nearly a century.
It wasn't until the 1990s that researchers began seriously studying the anatomical differences between male and female cyclists—and what they found was sobering. The female pelvis is not simply a scaled-down male pelvis. It is structurally different in ways that matter profoundly for saddle design.
What the Anatomy Actually Looks Like
Here's what decades of research have confirmed:
- The sit bones are wider apart. A woman's ischial tuberosities—the bony protrusions you sit on—are typically spaced 130 to 155 millimeters apart. For men, the range is more like 100 to 120 millimeters. This means a saddle designed for a male rider will often place a female rider's weight directly onto soft tissue rather than bone.
- The pelvis is shallower. This changes how weight distributes across the saddle, particularly at the nose. Female riders tend to experience more pressure on the pubic symphysis—the joint at the front of the pelvis—especially when riding in an aggressive forward position.
- The soft tissue is more vulnerable. The labia, clitoris, and surrounding structures are highly sensitive to sustained pressure. Unlike the male anatomy, which can shift position more easily, female soft tissue is more fixed in place—meaning it takes the full force of whatever pressure the saddle delivers.
- Hormones change everything. Throughout the menstrual cycle, hormonal fluctuations affect ligament laxity and tissue sensitivity. A saddle that feels fine during one phase of the cycle may become unbearable during another.
The numbers bear out the severity of the problem. In one survey of female cyclists, 35 percent reported vulvar swelling after rides. A 2023 study found that nearly 50 percent of women who cycle regularly had experienced long-term genital swelling or asymmetry. Some have undergone surgical procedures to repair tissue damage caused by years of riding on ill-fitting saddles.
The Cut-Out: Progress, But Not a Solution
The introduction of central cut-outs and pressure-relief channels was a genuine advancement. By removing material from the perineal area, these designs reduced pressure on the pudendal nerve and improved blood flow. For many women, this was the first time they could ride without numbness.
But cut-outs alone cannot solve the fundamental problem of width.
Imagine a saddle with a generous central channel but a rear section that is too narrow for the rider's sit bones. The channel relieves central pressure, but the rider's weight still falls on soft tissue on either side of the channel. The result: labial pressure, inner thigh chafing, and discomfort that simply shifts location rather than disappearing.
This is where the limitations of fixed-geometry saddles become clear. A saddle that is the right width for one woman may be wrong for another. A saddle that works for a rider at the beginning of the season may become uncomfortable after weight changes or increased flexibility. And a saddle that feels good on a trainer may be unbearable on rough roads.
A Different Approach: Adjustability as the Missing Piece
This is where Bisaddle's design philosophy offers a genuinely different solution.
Rather than selling a fixed shape in multiple sizes, Bisaddle creates saddles that the rider can physically adjust. The saddle consists of two independent halves that can slide closer together or farther apart, changing the overall width from approximately 100 millimeters to 175 millimeters. The gap between the halves—essentially a custom-width central relief channel—can be set to whatever dimension the rider needs. Each half can also be angled independently, allowing for fine-tuning that fixed saddles cannot provide.
For a female cyclist, this adjustability addresses the core problem directly:
- Widen the saddle to match her specific sit bone spacing, ensuring weight is carried by bone rather than soft tissue
- Create a central gap that relieves perineal pressure without compromising support
- Adjust the angle to accommodate pelvic asymmetry or changes in riding position
- Reconfigure as needed when her body changes due to training, weight fluctuation, or hormonal cycles
This last point is critical. Female bodies are not static. They change throughout the month, throughout the season, and throughout a cycling career. A fixed saddle, no matter how well-chosen at the point of purchase, cannot adapt to these changes. An adjustable saddle can.
The Hidden Cost of Discomfort
There's a persistent belief in cycling that comfort and performance are opposing goals. The logic goes: a more comfortable saddle must be softer, wider, and less efficient—a trade-off that serious riders should avoid.
The evidence suggests otherwise.
When a rider is in pain, they shift. They move forward, backward, side to side—any motion that relieves pressure. These micro-adjustments, repeated hundreds or thousands of times over a long ride, disrupt the pedal stroke, increase aerodynamic drag, and waste energy. Studies have shown that riders experiencing perineal discomfort produce less sustained power and report higher perceived exertion at the same workload.
For female athletes, the performance cost is compounded by avoidance. Many women simply refuse to ride in certain positions—the drops, the aero tuck, the aggressive forward lean—because of saddle discomfort. This limits their ability to optimize aerodynamics and power transfer, effectively capping their performance potential.
A saddle that genuinely fits eliminates the need for these compensations. The rider stays in position longer, produces power more consistently, and finishes rides with energy to spare rather than pain to manage.
What to Look For
For female cyclists evaluating their saddle fit, the following factors matter most:
- Sit bone support above all else. The saddle must be wide enough to support the ischial tuberosities. This is non-negotiable. If your sit bones are not carrying your weight, your soft tissue is—and that will eventually cause problems.
- Adequate central relief. Whether through a fixed cut-out or an adjustable gap, the perineal area must be free of sustained pressure. The width of this relief should match your anatomy, not a generic template.
- Firm, supportive padding. Counterintuitively, softer is not better. Excessive padding allows the sit bones to sink into the saddle, causing the nose to tilt upward and press into the perineum. Firm padding distributes weight evenly and maintains the saddle's intended shape.
- Short or adjustable nose length. A long nose places pressure on the pubic symphysis and soft tissue, particularly in forward riding positions. Shorter noses—or adjustable designs that effectively shorten the nose—reduce this pressure significantly.
- The ability to adapt. Given the variability in female anatomy and the changes that occur over time, a saddle that can be adjusted offers long-term value that fixed designs cannot match.
Looking Forward
The cycling industry is slowly waking up to the reality that female riders have been underserved. More brands are offering multiple widths, gender-specific models, and pressure-relief features. But the fundamental limitation remains: most saddles are still fixed shapes that ask the rider to adapt to the saddle, rather than the other way around.
Bisaddle's adjustable approach inverts this relationship. By giving the rider control over width, angle, and relief channel, it acknowledges a simple truth: no single shape can fit every rider, and even a perfect fit today may not be perfect tomorrow.
