The Effect of Ankle Dorsiflexion on Sagittal Posture and Core Muscle Activation

Abstract

Maintaining proper posture is essential for preventing musculoskeletal disorders and reducing injury risks. This study investigates the impact of insoles with ankle dorsiflexion (inverted drop sole) on sagittal posture, spinal curvatures, and core muscle activation. Methods: Fifty-five participants (29 men, 26 women; aged 20–70 years) were evaluated in two conditions: barefoot and with insoles incorporating an inverted drop sole. Kinematic data of trunk, hip, and knee angles, along with spinal curvatures (dorsal kyphosis, lumbar lordosis, and sacral slope), were collected using the Simi Aktysis 3D system and the Medi Mouse IDIAG 360®. The electromyographic (EMG) activity of the rectus abdominis and rectus femoris muscles was analyzed using the Bioplux® device. Statistical analyses were conducted using Wilcoxon tests (W) for non-parametric data and Student’s t-tests (T) for parametric data with significance set at p p = 0.009 and p p = 0.162) was observed. Spinal curvatures, including dorsal kyphosis, lumbar lordosis, and sacral slope, significantly decreased (p rectus abdominis and rectus femoris muscles (p rectus abdominis and rectus femoris (rB = −0.82, and ES = −0.82, respectively). Conclusions: Insoles with ankle dorsiflexion significantly improve sagittal posture by reducing spinal curvatures and enhancing core muscle activation. These findings suggest that dorsiflexion technology in footwear may serve as a non-invasive strategy for improving posture, preventing musculoskeletal disorders, and managing low back pain.

Keywords

• kinematics
• gait
• electromyography
• spinal alignment
• inverted drop sole
• low back pain