Influence of Saddle Height on Lower Limb Kinematics in Well-Trained Cyclists

Jed Williams Research Review

An Evaluation of current measures for static analysis of saddle height look at both trochanteric height; the distance from the ground up to the grater trochanter, the bony land mark on the top of the femur, and inseam, the distance measured from the ground to the ischium. When using the inseam to measure saddle height, previous studies have suggested using a range of 106-109% of inseam, when saddle height is measured from the centre of the pedal axel to the top of the saddle if the crank is in line with the seat tube.

Static goniometer readings suggest optimal knee angles in static conditions are 25-35º, research has shown that a knee angle of 25º is a great predictor of improved aerobic performance. Dynamic analysis has been found that lateral pelvic tilt from rocking on the saddle increases the acceptable range of knee flexion to 30-40º and that a saddle height of 106-109% does not always produce a dynamic knee angle of 30-40º.
The researchers planned to compare a group of well-trained cyclists with one group whose saddle height was in the range of 106-109% of inseam height and one group who were outside of that specific range. The first group who were within the 106-109% range resulted in 50% of the population with knee angles outside of the desirable range. Whereas the second group all of whom had saddle heights >109% of inseam height only had 7.7% of the population outside of the desirable range for knee angles.

The findings from this study show that static and dynamic methods for selecting saddle height do not necessarily coincide with one another. It is also worth noting that old studies which suggested the 106-109% of inseam range were all conducted with the use of toe clip pedals and that with the use of clipless pedal system an adjustment should be made for pedal stack height.



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The study suggested a change to using 108.6-110.4% of inseam height to accommodate for the use of clipless pedal system. They also proposed their own formula for calculating saddle height.

SH=22.1+(0.896×E)-(0.15×KA)

SH=saddle height,

E= inseam in cm,

KA= desired knee angle


A limitation with this study is that there is no standardisation mentioned across saddle and while saddle setback is mentioned it is not taken in consideration while measuring saddle height so there is no way of knowing if all participants were sat on the same place on the saddle meaning that each cyclists effective saddle length could potentially be different to the measured value.

Ferrer-Roca, V., Roig, A., Galilea, P., & García-López, J. (2012). Influence of saddle height on lower limb kinematics in well-trained cyclists: static vs. dynamic evaluation in bike fitting. The Journal of Strength & Conditioning Research26(11), 3025-3029.

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