Monitoring the body's center of mass (BCoM) during real-world activities is vital in biomechanics and rehabilitation. It helps identify musculoskeletal disorders, assess energy use, and evaluate balance and mobility. An inertial measurement unit (IMU) can measure vertical BCoM movement by integrating accelerometer data, but this method can be inaccurate over long periods due to accelerometer biases and initial assumptions. To address these issues, this thesis integrates a barometer, traditionally used as an altimeter in avionics, into a wearable multi-sensor system that includes an IMU. The barometer is incorporated at both the hardware and firmware levels, and its readings are fused with the IMU data using sensor fusion techniques.