BCSM – The Ultimate Bike Fit
A while back, I had the opportunity to visit the Boulder Center for Sports Medicine, home to Andy Pruitt and his gang of cycling experts. I’ve posted about Andy before and how his books have been very helpful in assisting me in ridding myself of many of the aches and pains that are associated with long distance riding and, ahem . . . age. Of the many services BCSM provides to athletes (or in my case, people who think they’re athletes), bicycle fitting is a big part of their stock-in-trade.
As all serious riders know and some less serious riders should know, bike fit is critical to efficient and fun riding. Trust me, if your bike doesn’t fit your body well, your bike’s gonna win the battle over the long haul and it just won’t be fun to use. For those interested, comfort on the bike is also highly correlated with performance. As, of course, is the dynamic between an individual’s musculoskeletal system and the geometry of the bike.
Having fractured my neck several years ago in an accident. I have somewhat limited range of motion in my neck and shoulders. That makes it a bit harder to get a bike to fit me well. I have had many fittings before and ride a custom bike (Seven Elium). I’ve been having some difficulty doing long rides recently, though, and thus my desire to seek out Andy and his team.
At BCSM, Andy does, among other things, a 3D bike fitting. Passive sensors are placed on the rider’s body and video recordings are taken of the rider as he/she pedals their bike in a stationary trainer. The result is pictures like the one below.
What a mess. In the picture, 1 is the motion of my left knee. 2 is the motion of my right knee. 3 and 4 are my left and right feet, respectively. So, my left knee moves from inside my foot to outside of it during the pedal stroke and my right knee stays inside my right foot during the entire stroke. As you can imagine, ideally, you’d like to have your knees and ankles aligned through the entire stroke. When they’re not, you lose efficiency and, like me, start having knee problems.
Andy changed my seat height, decreased the length of my stem (the tube that attaches your handlebar to the steerer tube – where your front fork attaches to your frame) and built up orthotics for my shoes. After making these adjustments, my knees looked slightly better (the muscles in your legs have to be retrained for the changes). More interestingly, my cadence picked up about 10-15 RPM at the same power level (good thing – I could spin faster, which makes pedaling easier).
I’m not sure where my knees are now, a couple of months after the changes. Subjectively, they look like they’re in a better position. They feel a lot better, though. The other changes BCSM made have made my overall riding experience a lot more comfortable and I’m riding faster this spring than I was riding last fall. All good.
If you’ve never had a fitting, any good local bike shop can do one. They won’t use cameras, lasers and computers, but they can probably make your bike better with a few simple adjustments. It doesn’t cost a lot, either. If you’re heavily into riding, you probably have had bike fits before. If you find yourself in the Boulder area, you may want to have one done at BCSM. My fit also gave me parameters for a new bike when I get one. It’s certainly more expensive than a bike shop fit, but if you’re serious, it can make a big difference.