Effect of Hip Angle on Spinal Curvature during Rod Exercise

[Purpose] We investigated the effect hip flexion angle has on spinal curvature during rod exercise. [Subjects] The subjects were 40 healthy adults aged 21.1±0.5 years. [Methods] We measured thoracic kyphosis and lumbar lordosis angles in standing still (Condition A), as well as at hip flexion angles of 0° (Condition B), 30° (Condition C), 60° (Condition D), 90° (Condition E), and 120° (Condition F) during performance of the rod exercise, and compared the six conditions. [Results] Thoracic kyphosis in Condition A showed a significantly smaller value than those of all the other conditions, and was significantly smaller than Condition F in Condition B. Lumbar lordosis showed a significantly larger value in Condition F compared to all the other conditions, and showed a significantly smaller value than those of all the other conditions, except for Condition B, in Condition A. [Conclusion] Increasing the angle of hip flexion in the rod exercise can extend the thorax by restricting lumbar extension.