Effect of saddle height on the lower extremity kinematics during the cycling: simulation by OpenSim

Poster Presentation
Paper ID : 2161-SSRC
Authors
ورزشی تحقیقاتی
Abstract
Introduction
The cycling is modern sport that many parts of that can be manipulate. The big challenge of this sport is adjustment of the saddle height. Previous study analyzed the saddle height from different viewpoints. Although, there are lack of study in kinematics analysis via musculoskeletal modeling in hip, knee, and ankle joints. Consequently, the aim of this research was to compare lower extremity kinematics by musculoskeletal modeling for two different saddles during cycling.


Research Question
What is the effect of saddle height on lower extremity kinematics during cycling?


Methods
Twenty professional athletes participated in this study (Mass: 75.3±6.5 kg, Heights: 180±6.3 cm, Age: 28.5±6.5 years). Ten Vicon motion captures (Vicon MX, Oxford, UK, 100 Hz) were utilized to record the markers positions. The smart trainer (Tacx Flux, Netherland) was used to measure output power of bicycle. The inseam quantity (the distance from the uppermost of part of thigh to ankle) of each subject measured and then multiply to 0.883 to find standard saddle height that was choose as lower saddle. Then, we added the 4% to lower saddle height that was choose as upper saddle. The cadence remains at 60 rpm for times of cycling. The full body model used as base model in OpenSim. The personalized model created for each subject by scaling tool. The lower limb joint angles were calculated by inverse kinematics tool in OpenSim.

Results
the mean and standard deviation of lower limb kinematics for two different saddle heights calculated during the cycling. The significant differences of hip angles between lower and upper saddle were found (p<0.05). Additionally, changing the saddle height alter the peak angles of hip. The knee angles of lower and upper saddle were similar.

Discussion
This attempt is basic research for compare two different saddle height to find how hip, knee, and ankle joint influenced by saddle height. Based on the results, the main effect of saddle heights is in the hip and ankle kinematics. Rising the saddle height increased the hip flexion while minimum differences were observed for knee angle. The future study can compare more saddle heights during cycling.
Keywords