• Admin

Mirinda Carfrae: Detailed Fit Analysis

By: Mat Steinmetz

Last week, Slowtwitch.com published a short overview of the below piece. There are some good discussion points in the comments section below the article. Please use the contact form if there are anymore questions or if you'd like me to elaborate on something.

I’ve worked with Rinny on her bike position since 2009 and it has been a work in progress over the years. Rinny will be the first to admit that she’s not quick to adapt or break old habits on the bike...so, I’ve not moved as quickly with her as I would with others.

I’ve tried a few things that didn’t stick over the years. It doesn’t mean it was right or wrong, but if you don’t believe in something, it’s hard to take the risk. When dealing with an athlete that has been as successful as Rinny, you need to make sure you have a good reason to change anything. She has always had an open mind and willing to at least try something new. Like anyone else, she is always looking to improve.

There will be no changes to Rinny's fit coordinates this year...Good luck getting someone who just broke the Kona course record to change something. It works, it’s comfortable, it’s relaxed, aero, and she obviously runs well off it. Could there be some adjusting? Sure, there is always something that can be adjusted. The thing with Rinny, is that her form and technique is still improving on the bike.

Posture improvements: Just because the fit coordinates don't change, doesn't mean the position won't look different. An athlete can learn and practice sitting on the bike in a more relaxed and aerodynamic posture. It just takes practice. Not everyone hops on a bike and looks like a natural...it takes work.

I often compare making gait modifications (change in form, technique, posture) to technical sports such as swimming or golf. When correcting a movement pattern, it might sometimes get worse before it gets better. The body is great at adapting...even if it’s adapting to a less favorable position. It takes trust and confidence to see changes through.

Upper Arm Angle (Reach)

I’m moving away from the vertical upper arm. I believe a slightly more stretched out arm allows for a more relaxed position through the arms and shoulders. I also believe this helps the athlete drop their head to become more aerodynamic. *Note: You need to be careful to not stretch the athlete out too much...they still need to be supported skeletally.

Saddle Change

I also think swapping to an ISM saddle was a big deal for Rinny. It’s partly why she can now relax her upper body and lay out across the bike. Her previous saddle forced her to come forward attempting to displace weight off the saddle and onto the front end.

Anterior Pelvic Tilt

The change to the ISM (Attack) allowed Rinny roll her hips forward instead of up under her to relieve saddle pressure/discomfort.

Pedal Mechanics

Rinny used to pedal squares and had a massive heel drive (pictured). I typically don’t have a preferred ankling style, but find myself having to correct a lot of athletes who’ve been told to keep their heel down. When rotated forward in the TT position, a flat, 90 degree ankle, will appear to be toe down and is perfectly normal.

Power Phase

For simplicity, I'll define this as when a rider is pushing down on the pedals. This heel drive would have Rinny exiting the power phase of her pedal stroke early. If you look at the two pictures above, you will see what I'm talking about. The crank arm is close to being in the same position in both picture, but they look totally different. In the pic titled pedal mechanics, the power phase is complete and the knee is extended. In the pic directly above, she is still in the power phase and will be until she is close to 6 o'clock if you view the crank as a clock.

Dead Spot

Rinny's old pedal stroke extended the duration that she spent in what people call the "dead spot" of the pedal stroke. To get through this spot, she’d pull back and up during the recovery phase, creating a choppy pedal stroke.

Fit Coordinates and Biomechanical Data

Contact Us to schedule a fit at one of our two locations...Boulder, CO or Indianapolis, IN


1 view0 comments

Recent Posts

See All