Has anyone had a chance to read and evaluate the article “Triathlon Bike Fit: A Detailed Primer” in the latest (August) edition of Triathlete Magazine?
I attended one of the first workshops at FIST. I also work in a small shop trying to combine aerodynamics and comfort to some of our local athletes. I have a small group of successful Ironman Kona qualifiers that I have fitted who love the position I have put them in. I also have some triathletes that don’t care for the “aggressive” position but insist on top of the line steep angled bikes.
As I look at the accompanying photo, which I searched for on the magazines website to no avail, a couple of things just look funny to me and I wonder how valid they are in assessing a good fit to a Triathlon Race Bike. Perhaps it is my ignorance on some of the finer points of biomechanics, nevertheless, here is my assessment of the position of the athlete in that article. Saddle height: should be measured at the bottom of the pedal stroke not at the 6:00 position. The photo indicates the athlete is a bit off. The angle of the leg is about 155 degrees but the athlete is not at the bottom of the stroke. Saddle is too high. I realize that I am not there and assessing a picture. Saddle set back: The athlete is sitting on the nose. If it is a question of comfort, move the saddle underneath the sit bones (ishial tuberosity). This could go either way I suppose, but my experience has been positive in regards to setting the saddle under the rider’s sit bones. Plumb line: having a perfect line between the knee and the pedal axle is difficult to attain in a forward position. It is usually a bit in front of the axle. Hip Angle: The photo shows the intersection of the rotation at the top of the knee. I have always lined the hip bone (Greater Trochanter) with the pedal axle. So, my 90 degree angle is based on the shoulder joint, hip joint and the pedal axle/ball of foot at the bottom of the pedal stroke. Perhaps I am wrong. Reach to bars: I think that the athlete’s reach is acute. I try to keep a 90 degree angle from the torso to the to the upper arm, rotating at the shoulder joint. I believe the athlete is putting too much pressure on the front deltoids. After an IM swim this is the last place I want fatigued.
What would I do different? I would change the angles, I would put the seat underneath her and I would drop the saddle, unless I am just not seeing the pedal line properly. These changes will give a lower profile without sacrificing biomechanics. Before I take my allen key to the bike though we are going to have a discussion in terms of goals, fitness level and flexibility. After that assessment we can move into getting the athlete into a position they will appreciate.