A Prototype Validation Study of a Digitized Pressure Biofeedback Unit Versus Electromyography During Transverse Abdominis Muscle Activation

Core stability, particularly involving the Transverse Abdominis (TrA) muscle, is essential for lumbar support and is especially relevant for individuals with lower back pain. Traditional Pressure Biofeedback Units (PBUs) are commonly used to monitor TrA activation during core stabilization exercises but these analogue devices have limitations in terms of monitoring usability, often requiring manual readings prone to error. This study aims to develop and test a digitized Pressure Biofeedback Unit (PBU) prototype specifically for monitoring transverse abdominis (TrA) muscle activation, enhancing accuracy and providing real-time digital feedback for clinical and rehabilitation settings. The prototype integrates an Arduino microcontroller and a barometric pressure sensor to capture TrA activation automatically, reducing manual operation. Readings of the PBU prototype were then evaluated by applying loads weighing 1 to 3 kg and compared against the pressure gauge. Six healthy male participants (mean age 24 ÷ 2 years) performed abdominal draw-in manoeuvres at targeted pressures of 50, 60, and 70 mmg, with muscle activation recorded via surface electromyography (EMG) and PBU. Results indicated that the root mean square error (RMSE) of dPBU ranged 0.15 to 0.94mmHg at baseline (i.e. no load) and with loads up to 2kg only, affirming the dPBU's accuracy in detecting TrA activity. Additionally, a positive trend showed between the PBU and EMG measurements with dispersion less than 0.5mmHg across different levels of muscle activity suggests that the PBU could serve as a reliable, user-friendly alternative to EMG biofeedback in core stabilization training, supporting efficient TrA monitoring and activation in clinical rehabilitation.