Cyclist Flexibility And Bicycle Design

Read full article by Georgena Terry here

Q: How much does a cyclist’s flexibility factor into a bicycle design?

A: Before a customer purchases a bike from me, I ask her to complete a questionnaire that covers everything from measurements of herself and her current bike, her cycling aspirations and her flexibility. If you’ve followed the evolution of fitting techniques, you’ll know that flexibility is becoming as important as an inseam measurement for setting up a properly fitting bicycle.

Achieving a “neutral” or flat back position can be difficult if the hamstrings are tight. These muscles attach to the pelvis at the ischial tuberosities (sit bones) and behind the knee joint. If they’re tight, they pull down on the pelvis, causing it to rotate back. On the bike, this often leads to a rounded back, which can cause neck pain from rotating the head up to watch the road. The upside is that rotating the pelvis back reduces pressure on the sensitive “bits” that land on the front of the saddle.

hamstring-musclesIt’s easy to see how a rider who is flexible can have an advantage over a rider who is not as flexible, since the former will be able to get into a lower and longer position on the bike. In this position, the rider is more aerodynamic and can generate more power than a rider sitting upright. The pelvis rotates forward, allowing the spine to settle into a neutral position, reducing the possibility of low back pain. The downside is that there is more pressure from the saddle on the rider’s crotch.

Jo McRae, a trainer in the U.K., distinguishes between the “upper” and “lower” hamstrings. She maintains that as a cyclist pedals, the upper part of the hamstring, which connects to the pelvis, is stretched more than the lower end of the hamstring at the knee. [Bike Fit Blog Part Deux,]  As a result of this dynamic motion, the upper end of the hamstring tends to be more flexible than the lower end. Specific stretching exercises are needed to address that area.

Hamstring flexibility, or lack of it, affects saddle height. A rider who has tight hamstrings might not feel comfortable with the saddle at the high end of the range, but this can be addressed by stretching to improve hamstring flexibility.

Flexibility has an important role to play in how the bicycle can be set up most effectively for you. In the end, it’s up to you to decide what the proper trade-offs are between comfort and power.

Marx LogoWant to be more flexible but not too sure how to go about it? Follow Monika Marx’s stretches program each day after a workout or before bed. Take it from a non-bendy person, it will do you wonders! Check it out on YouTube here.