Bike fit: Case study
We have been getting some fantastic results with our specialised bike-fitting and musculoskeletal bike screening service, and decided to share an example with you all!
Case Study 1:
Gary is a 30 year old graphic designer, who commutes daily on his Giant Roadbike, and completes longer rides on weekends.
He came in for a comprehensive bike fit, as he was experiencing hip and lower back pain both on and off the bike. He had sought some treatment for these issues, but any relief of pain was short lived and would flare up again as cycling increased.
Gary’s Cycling-Specific Musculoskeletal Assessment identified some stiffness in his right hip flexors, pain on forward movement of the low back, and some tightness in both hamstrings.
Initial Biomechanical Assessment Findings
- excessive knee and hip flexion at bottom of pedal stroke – this can lead to knee pain, hip pain and reduce the effectiveness of the powerful hamstring muscles
- excessive drop on the right side of the hip during right pedal stroke – leading to the compressive low back and hip issue that he was experiencing
- knee rotation towards the midline during downstroke – strain on medial knee structures, and minimising efficiency of pedalling/power output
Gary’s bike required a significant raise of the seat height, to account for the increased flexion of both knees (angle was 115 degrees at bottom of stroke – should be between 140 and 150 degrees), forward position of knee over pedal axis, and prevent using the back muscles to increase power of pedalling, due to the poor position of the knees and hips.
As seen in the above still shots, a large improvement in knee joint angle is seen following the adjustment. Also, the alignment of the patella over the pedal axis is improved greatly.
Gary would benefit from a further 45mm raise, however tolerance to this initial change would need to be reached before the seat is raised further.
Since Gary has completed his Comprehensive Bike Fit, he does not experience any hip or back pain during cycling, and has described “feeling smoother pedalling, particularly up hills.”
Gary has since returned for the further 45mm increase, and since is planning to compete in the upcoming Gatorade Triathlon Series. We wish Gary all the best for the upcoming events!