Asymmetry & Bike Fit - The Pelvis

I think a crucial missing piece to most bike fits is an assessment of pelvic stability while riding under load. 

Steve Hogg, a fitter out of Sydney, writes about it often on his blog: http://www.stevehoggbikefitting.com/blog. In sum, no one is 100% symmetrical is structure or function.  The people who function most symmetrically on a bike generally can train harder and longer without injury.  Here is a post with a video showing a severe case.  You probably aren't this bad, but just about everyone could use correction. 

So if you function asymmetrically, your bike fitter should adjust your fit to accommodate the way you function.  This can be accomplished through moving your saddle to the left/right with an FSA seat post with a data head, by twisting your saddle to the left or right slightly, by shimming one shoe to make it longer than the other, wedging one or both cleats/shoes, or by other methods. 

I am a devoted reader of Steve's blog, mostly because I have been struggling with cycling injuries for the past 7 years.  I think it is a good use of your time if you also struggle.

And to give a personal example, shimming seems to be helping me.  I have an x-ray verified leg length discrepancy (left tibia is 18mm shorter than my right one).  It turns out that shimming my right cleat (I know, opposite of what you would think) allows my pelvis to function more symmetrically on the bike seat.  I tried shimming the left cleat for the past 6 months and it felt worse than no shims...but with the right cleat shimmed I immediately felt more symmetrical.

I have not been able to apply more than 80% effort on the bike without severe left calf cramping and soreness for years.  Now with the right cleat shimmed, I am riding at 95% effort with only minimal soreness the next day.  Still have some details to work out, but I feel like I'm on the right path (finally).