Evaluation of Dynamic Spinal Morphology and Core Muscle Activation in Cyclists-A Comparison between Standing Posture and on the Bicycle

(1) Background: Cycling is characterized by a sustained sitting posture on the bicycle, where physiologic spinal curvatures are modified from standing to cycling. Therefore, the main objective was to evaluate and compare the morphology of the spine and the core muscle activity in standing posture and cycling at low intensity. (2) Methods: Twelve competitive cyclists participated in the study. Spinal morphology was evaluated using an infrared-camera system. Muscle activation was recorded using a surface electromyography device. (3) Conclusions: The lumbar spine changes its morphology from lordosis in standing to kyphosis (lumbar flexion) when pedaling on the bicycle. The sacral tilt significantly increases its anterior tilt when cycling compared to when standing. The spinal morphology and sacral tilt are dynamic depending on the pedal's position during the pedal stroke quadrants. The infraspinatus, latissimus dorsi, external oblique, and pectoralis major showed significantly higher activation pedaling than when standing, although with very low values.

Automated summary

This study analyzed the spinal morphology and core muscle activity of cyclists in both standing and cycling postures, revealing differences in the shape of the lumbar spine and anterior tilt of the sacrum between the two positions. Additionally, certain muscles showed significantly increased activation during cycling compared to standing, despite relatively low values.