After having an infection that was linked to bike riding and saddle type I spent some time investigating a replacement saddle. Most people, myself included, did not understand how a bike seat is meant to work. Basically you "perch" on your sit-bones, with very little else in contact with the seat. Most larger gel seats allow you to squish down into them and this cuts off pubic blood flow.
Specialized make a saddle called the ALIAS that has three different widths for different pelvic widths and have some description of restricted pubic blood flow caused by improper saddles. Wider and more comfy is definitely not the best result for longer rides. I ride 500klms+ a week at the moment on a SLK saddle which is very slim and has a central cutout.
I am not specifically advocating Specialized, however have a read of what they have to say under their saddles and body geometry.
When it comes to saddles there are essentially four variables you can play with.
1. Saddle Type
2. Saddle Tilt
3. Saddle Height
4. Saddle Fore & Aft Position.
1 Saddle Type
An article in “Outside” Magazine Sept 2004 quoted recent studies from Prof. Frank Sommer, Professor of Urology at Germany’s University of Cologne Medical Center that has shed new light on what was long suspected in the cycling world.
Blood flow to the pubic area including the prostate is severally affected by saddle type.
Of the 19 different seats he evaluated to find out which ones outshined traditional solid, dome shaped saddles, which allow an anemic 20% blood-circulation flows, the top performers demonstrated blood flows above 70%. The best four performers, not in order, were
1) Specialized BG2 Comp Pro (US$80) 877-808-8154
2) Terry Precision Cycling, Fly Ti for men (US$110, 800-289-8379
3) Selle Italia SLK Gel Flow (US$135, 800-279-3793,
and other Internet sites
4) Specialized ALIAS, reported to improve blood flow by 400% over traditional saddles (i.e. 4 x 20% of traditional, or 80% of normal blood flow) (US$99.99)
Cyclists who suffer from loss of blood flow to the pubic area or simply want to be proactive and avoid aggravating men’s health problems into the future should buy a saddle that promotes circulation. It sounds counter intuitive, but Sommer found that the cushier the seat, the more you sink into it, and thus, the more you constrict the arteries.
I changed my Saddle to a Selle Italia SLK and noticed a marked improvement straight away. This, plus the habit of standing in the saddle to allow blood to flow freely again is all part of avoiding illness and injury.
2. Saddle Tilt
This is the easy one of the four. Simply set the saddle up level with the ground. Place a bubble level on the seat in line with the frame. If you have a cutout seat like those above, place a small bridging piece across the rear and the front then set it up level.
3. Saddle Height
There are many different techniques for adjusting saddle height. In Dr Edmund Burke’s excellent publication “Serious Cycling” he describes three methods that all give much the same result. For interest’s sake, these are, The John Howard Method, The Greg Le Mond Method, and the Andy Pruitt Method. For expedience the Greg Le Mond method is repeated here.
Greg Le Mond says that you should multiply your inseam length in centimeters (measured in stocking feet from floor to crutch) by 0.883. Measure yours by standing with your back against the wall and your feet about 15 cm apart. Put a carpenters square or record album snug against your crotch, exerting the same pressure as your saddle would. One edge should be flat against the wall. Have a friend measure from the top to the floor.
The product of this equation should equal the length from the center of the bottom bracket axle to the top of the saddle. If you have clip less pedals, Le Mond recommends subtracting 3 mm from this measurement to get your saddle height.
4. Saddle Fore and Aft
Although it has limited effect on blood flow to the pubic area, it has a significant effect on knee related injuries. A long-standing recommendation for achieving saddle horizontal position is to check that your knee is perpendicular over the pedal spindle.
This is best achieved with the bike set up on a wind trainer and the front wheel lifted to set the bike on its normal level. Sit on the bike, with hands on the drops, in a racing position with the pedal crank at 3 o’clock or the horizontal position.
Have a friend locate the bony protrusion below your kneecap and drop a weighted string line (plumb line) from the knee. Slide along the saddle until the string line and the pedal axle line up, then dismount and move the saddle forward or backwards on the pedal rail to suit your new position. Your foot should be in its normal position, not raised or lowered. If you cannot achieve this position by moving your seat within the seat adjustment, then, your handlebar stems are incorrectly sized. You may also find the handlebars now appear too high, in which case you need to remove the stem spacers from under the stem and place them on top. Look at any serious road cyclists and you will notice the bar stem is always lower than the seat level by some inches. This helps with not only the aerodynamics but also the correct positioning of the knee over the pedal spindle.
All of the above merely represents tips and advice gathered “along the road”. Get yourself a saddle that promotes blood flow. Take some time to set yourself up properly on the bike and you will be rewarded with injury free cycling. Nothing can replace good advice from an experienced bicycle positioner and it is money well spent.