Unlocking the Secret to Bike Fitting
Of all the different things a fitter can do to manipulate you and your bike I believe there is one aspect that stands out above all else…
Why? Pelvic rotation is the by-product of a well set-up “back-half” of the bike. By this I mean a correct saddle height, for/aft and proper saddle tilt along with the correct saddle. When these factors align, then we have our pelvic rotation.
What is Pelvic rotation? In simple terms, it is the orientation of the pelvis in relation to our thighs. A posteriorly rotated pelvis makes it very difficult to achieve any sort of maintainable performance-based position, especially when attempting to get down into the aero-bars. In order to overcome this poor rotation, the flexibility of our lower backs, hamstrings and glutes steps in, something that many of us do not possess in great amounts.
That leaves us with the big question of how do we get this “anterior pelvic rotation”. As I mentioned above, there are four factors that come into play. Saddle height, saddle for/aft, saddle tilt and the type of saddle itself.
For saddle height and for/aft, I cannot offer any generic advice, as it simply doesn’t exist. With saddle tilt, (which I will touch on more next time) the golden rule of bike fitting is to have stable contact points. This means your saddle must be level (note: every saddle has a different definition of “level” and its not always perfectly horizontal). A saddle pointed skyward will ruin pelvic rotation and cause untold pain to yourself and your unborn. A downward pointed saddle will artificially create the illusion of pelvic rotation, while transferring all the untold pain into your upper neck and shoulders.
Now comes saddle choice. A number of saddle companies have come up with options to help improve blood flow in the perennial, promote pelvic rotation and improve comfort for triathletes, with notable contributions to ISM with their Adamo saddles, Cobb saddles, Bontrager’s Hilo and Specialized’s Sitero. I have had experience fitting all of these saddles to different bikes and all have their benefits, however the ISM Adamo range is by far the most consistent and most effective at achieving pelvic rotation. When set up correctly (and I mean really correctly…. they can be a little tricky), they almost guarantee pelvic rotation. The ability of achieving a nice aerodynamic position is far greater and the comfort when down on the bars is unparalleled. For anyone with aero-bars on a bike, they are almost an absolute necessity.
With that I will leave you for another addition, but if you have an oddly tilted saddle, find yourself getting a sore lower back or any form of numbness or pain in the nether regions, then I assure you, this is not normal, your flexibility (or lack thereof) doesn’t need to be a limiting factor in your bike fit and you need to have this addressed.