Debating Approaches
To accurately capture what all of this means to you, the reader, I've asked Stu Waring, a Master Retul fitter and instructor, his thoughts on the advantages and disadvantages of old-school methods versus high-tech methods. I trained Stu years ago using the PowerFiTTE methodology, but he currently uses the more tech savvy Guru Dynamic Fit Bike and Retul for all of his fittings. I consider him the person most knowledgeable to discuss the merits of both approaches.
JH: Hey Stu, hand fitters appear to have been unceremoniously swept to the curb by a tech savvy, effectively marketed array of glitzy technology. Have the "hands-on" fitters become anachronisms of a dying culture? Or just in need of better tools like the CompuTrainer SpinScan that essentially measure the fluid dynamics of the pedal stroke? Share some of your thoughts on the pros and cons of "Tech vs Hand."
SW: Well John, the main advantage in using a Fit Bike is that we can make adjustments to the rider's position in a dynamic state. Traditionally, adjustments using the client's bike can only be made in a static state. The rider had to stop pedaling, lift off the saddle or get off the bike while adjustments were made.
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The DFU that I use allows me to save multiple positions and quickly revert back and forth with a click of the mouse. With a hand fit, it's impossible to go back to another position without tearing the bike apart, which takes time. In regards to measuring the rider's position, the biggest variable with static fitting is that the fitter is required to stop the rider and position the foot at the bottom of the stroke to measure the knee angle.
The hand fitter has to set the foot, and therefore is putting the rider in a position that the fitter perceives as the most desirable and not how the rider actually pedals. This leaves the door wide open for inaccuracies. Retul measures the ankle angle and knee angle at the same time dynamically, which allows for the best position to be attained for the rider.
JH: OK, but with a good eye, an experienced hand fitter can watch the pedal stroke and do the same thing, right?
SW: I would have agreed until I saw how Retul works. Now I feel it is at best a good guess and not accurate.
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JH: I agree that replication of foot angles are important. We use a separate goniometer just to check the angle and a laser to measure the consistency of the angle. I believe my method is also accurate. I train my cyclists to pedal at 17 to 20 degrees of plantar flexion for maximum, consistent output. Another strong point concerns sacral alignment, which we check before measuring the leg angle.
SW: Like you, we are constantly looking and communicating with the rider during the entire process. This is something that you instilled in me years ago and is still a big part of my process.
JH: OK, we agree on visual observation. With the simplicity of a telescopic goniometer, I can check the body's trigger-point markers to get it right quickly, then back test the results with Computrainer's SpinScan (SS) technology.
SW: Yes, it's hard to argue the cost and simplicity of the goniometer. It's a classic tool and every fitter will always have one. A point on SS, it does not capture the entire stroke—it measures the torque output and calculates the information it provides on the first 180 degrees (down stroke) for each side.