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What To Expect When You're Bike Fitting

One of our clients, Grace, before (above) and after (below)

One of our clients, Grace, before (above) and after (below)

You just bought a bike! That's great. Congratulations. You're going to have a lot of fun on it. When you bought it, you probably had some idea on what size you needed, or the folks at the bike shop took a look at you and said "hmmmm...you're probably a 54," went over, found the model you'd settled your heart upon, rolled it over to you, had you sling a leg across the top tube, and said "Yep! That looks like it'll fit you." You went home, ecstatic and full of that New Bike Day feeling, better than New Car Smell by far.

After a month or so of riding, though, things start to feel a little...off. Your low back hurts a bit. Your shoulders are tight. Your neck is sore. After some initial soreness in your rear end, you're now beginning to experience some other discomfort in the—ahem—saddle section. Is this just riding a bike? Will you be sore forever? How come people like this so much? Am I really supposed to stay down in those aerobars for my whole Ironman?

The answer is no. Your bike should be comfortable. Yes, there is an acceptable amount of discomfort that comes from riding a bike, but it should be similar to the amount of discomfort you experience, say, from a long run—more effort-imposed than equipment-imposed. There will always be a little low level discomfort in sitting on a saddle made for racing a bike than from, say, sitting on your couch at home, but in general you should be totally down with the idea of sitting on your bike for four to six hours. Which brings us to the first thing you should expect while you're bike fitting...


Yup, comfort. In the picture above, Grace came in with some low back and hip discomfort. We looked at her existing position (the top picture) and thought that it was a bit stretched out. She was basically asking her low back to cantilever her torso out over the front end of the bike. So we brought the front end back towards her, raised it a bit, and angled her aerobars up to give her something to brace against. To our eyes, she looks quite a bit more relaxed in the second position—a little less jammed on the bike. We also shortened her crankarms, from 170mm to 165mm. This, we've discovered, is almost a no-brainer where it comes to making athletes more comfortable. With no loss of power, they make smaller circles when turning the pedals around the bottom bracket. Those smaller circles translate into a lower knee at the top of the pedal stroke (look at where Grace's knee is, vis-a-vis the back of the aerobar extension). By opening that hip angle, Grace felt less crowded when pedaling through 12 o'clock on the pedal stroke. So we achieved two different areas of greater comfort, which brings us to the second thing you should expect from a good bike fit...


Yup, more power. Turn it to 11! If you are more comfortable on your bike, you are just going to be able to generate more power (more Output!). You'll use the mid-range of your muscles' and joints' ranges of motion, which will directly translate into producing more power on the bike. Make more power, and what does that get you?


Speed! The thing we're all after. If you make more power, you're going to go faster (aerodynamics staying relatively the same). Sure, if you've gotten a little "taller" on the bike you'll sacrifice something to the wind, but those losses are likely to be slight. 

How do we get there?

So this is the real "what to expect when you're bike fitting." Well, a good fitter will follow these steps:

  • Look at your existing position, taking into account your existing physical abilities and structural limitations
  • Make small isolated changes, aiming to improve comfort
  • Track an athlete's relationship with his/her saddle, either through asking questions or saddle pressure analysis
  • Zero in a set of acceptable ranges where athletes have the greatest success
  • Listen to the athlete's feedback along the way, knowing that not everyone has the most success in those acceptable ranges
  • Arrive at a position that feels more comfortable to the athlete, using available technology to back up (not drive!) what the athlete feels and the fitter sees

Once the fitter pulls this off, you will be more comfortable on your rig, allowing you to generate more watts and to ride faster!

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