Author(s) :

Yaoshan Jiang.

Volume/Issue :

Abstract :

This study investigates the relationship between respiratory chest expansion and multi-axis body motion parameters measured using a wearable belt-like sensor equipped with an accelerometer and gyroscope. A chest-mounted elastic belt sensor simultaneously recorded three-axis linear acceleration, three-axis rotational velocity, and chest circumference displacement during a controlled breathing exercise performed by a single healthy participant in a seated posture (n = 1,282 observations). Pearson correlation analysis and multivariate linear regression were employed to quantify the associations among these seven variables. Results indicate that linear acceleration components, particularly along the vertical and lateral axes, exhibit moderate to strong correlations with chest expansion (r = 0.429 and r = −0.422 for the Y and Z axes, respectively, p < 0.001). Regression models for linear acceleration components demonstrated substantially higher explanatory power (R² up to 0.697) compared to rotational components (R² < 0.06), suggesting that translational body motion is more systematically coupled with respiratory chest expansion than rotational motion. These findings contribute to the growing field of wearable respiratory monitoring and demonstrate the feasibility of using low-cost inertial sensors to characterize breathing biomechanics.