Analysis of calf muscle contraction in various foot postures using an accelerometer sensor on a smartphone

The calf muscle acts as a "second heart"in the body, having an important function in pumping venous blood back to the heart through active contraction and relaxation. This study aims to observe and compare the contraction rate of the calf muscle in eight different leg postures. We took measurements using accelerometer sensors on a smartphone. We placed the first phone laterally on the lower leg, next to the calf muscle, and the second phone on the heel. We used the accelerometer sensor to monitor the contraction activity of the calf muscle as the foot posture changed. The recorded accelerometer data involved contraction signals that underwent filtering, feature extraction, normalization, and classification processes. Data analysis was based on calculating the amplitude and frequency of calf muscle contractions that predominate in each foot posture, with the use of thresholds to identify active and inactive muscle contraction activity. The results successfully identified and compared the level of calf muscle contraction in various foot postures, specifically highlighting that exercises 5, 6, 7, and 8 were effective in stimulating calf muscle contraction. These findings may contribute to improving calf muscle strength and function, as well as providing a deeper understanding of the correlation between foot posture and calf muscle contraction activity. In addition, this study also reminds individuals who tend to stay in a static position to move and exercise the calf muscles to maintain blood circulation and prevent vascular problems.