In recent years in Japan, AC (50/60 Hz) magnetic therapy has attracted attention for improving blood circulation and recovery from muscle fatigue. However, its effectiveness on poor circulation in the lower limbs due to sitting has not been verified. In this study, we verified the effect of an AC magnetic field on poor circulation caused by immobilizing the left lower limb in a sitting position (for 60 minutes) using an ankle weight (1.5 kg). Blood flow volume was measured using a two-dimensional laser speckle blood flow meter, and the left foot sole was exposed to a magnetic field (50 Hz, Brms 127 mT) for 10 minutes, and skin blood flow in the inner side of the calf and foot was monitored. The magnetic flux density (Brms) was strong at the forefoot (10 mT) and rearfoot (10 mT) of the foot placed on the magnetic field exposure device, but was relatively weak at the calf (0.2 mT). The blood flow volume values in the inner side of the calf and foot were significantly reduced by attaching an ankle weight compared with the baseline value (indicated as 100%). Magnetic field exposure significantly recovered these blood flow volume values, indicating significant differences between sham and magnetic field exposures. It was suggested that restoring blood flow volume throughout the lower leg, including the weak magnetic field exposure regions, may contribute to preventing deep vein thrombosis (DVT) caused by restraint of the lower limb.
OKANO et al. (Wed,) studied this question.