• Brian Hammond

What is a Dynamic Bike Fit?

What is a “Dynamic Bike Fit”?

A Dynamic Bike Fit refers to the tool that the fitter is using; is the fit occurring on a dynamic fit bike or is the athlete riding their bike (or another fixed bike). A dynamic fit bike is a bike that allows the fitter to move the bar and saddle position while the athlete is aboard the bike and pedalling. This means that as the athlete is riding we are able to raise or lower the saddle without having the athlete stopping their motion or moving off of the saddle; the saddle simple moves position while they are still seated on it. If we were to try to do this with the athlete's bike (or fixed bike) we would need the athlete to get off the saddle to allow us to raise or lower it which makes it much tougher for the athlete to directly compare the saddle height difference. The dynamic fit bike also allows to move the saddle forward and backward as well as doing the same adjustments with the handle bars.

By allowing you to remain on the bike while the saddle/bars are moved under you while you are riding allows you to directly compare the different positions. Do you like the saddle here or a little higher, do you like your bars here or a little closer? We can make minor adjustments, say 5 mm and you will directly feel the difference. If we have you get off the bike, move the saddle 5 mm and have you sit back down you most likely will not feel the difference, when it is moved while you are pedaling you will without a doubt feel the difference and will can compare which is feels more comfortable and powerful to you. The dynamic fit bike allows you to truly compare apples to apples.

Now do not confuse a dynamic fit bike with dynamic measuring, Remember that a dynamic bike fit refers to the fact that bike can move while the rider is aboard it; dyna

mic measuring refers to the tool used to measure the body angles while you are riding. Before we had dynamic measuring (Motion Capturing Systems) we as fitters relied on static measurement tools such as goniometers, plumb bobs and tape measures; now with Motion Capturing Systems like Retul and Dartfish we are able to use a video camera and software to measure all of the important angles like knee angle while you are riding. But remember this is nothing more than an easier way for the fitter to measure, it will not help you as the rider find the most comfortable position unless it is being used in conjunction with a dynamic fit bike.

With a dynamic bike fit you get to compare different positions with more detail because the bike moves under you rather than you moving over the bike. You get to compare apples to apples right there on the bike as you are pedaling. All you have to do is get on the bike, ride and answer the simple questions: Is this better or worse (as a part of the bike moves under you)?

Within just a few seconds we can easily compare different riding positions while you are pedaling to determine which gives you the most comfort and power. Our dynamic fit bike also has an integrated Computrainer system that allows us to track your power outputs and pedal efficiency in different positions as well. We also have the ability to test different crank lengths from 155 mm crank arms to 180 mm to find out which best suits your position.

#cycling #bike #bikefitting #dynamicbikefit #triathlon #roadbiking #granfondo


TruFit Solutions

143 West 72nd Street

New York, NY 10023